Tekanan

1. Pada gambar di bawah ini yang dimaksud permukaan bidang tekan ditunjukkan pada nomaor … .

2

3

4

The correct answer is 2 because in the given image, the surface of the pressure plate is indicated by the number 2.

Explanation

The correct answer is 2 because in the given image, the surface of the pressure plate is indicated by the number 2.

2. Berat benda di udara 70 N dan beratnya ketika dimasukkan ke dalam air adalah 25 N. Gaya apung yang dialami benda adalah … .

0,8 N

10 N

45 N

90 N

When an object is submerged in a fluid, it experiences an upward force called buoyant force. This force is equal to the weight of the fluid displaced by the object. In this case, the weight of the object in air is 70 N, but when it is submerged in water, its weight decreases to 25 N. The difference in weight (70 N - 25 N = 45 N) is equal to the buoyant force experienced by the object. Therefore, the correct answer is 45 N.

Explanation

When an object is submerged in a fluid, it experiences an upward force called buoyant force. This force is equal to the weight of the fluid displaced by the object. In this case, the weight of the object in air is 70 N, but when it is submerged in water, its weight decreases to 25 N. The difference in weight (70 N - 25 N = 45 N) is equal to the buoyant force experienced by the object. Therefore, the correct answer is 45 N.

3. Sebuah kapal laut yang terbuat dari baja dapat terapung di laut karena kapal laut … .

massa jenisnya lebih kecil dari air laut

mempunyai motor penggerak

volumenya sangat besar besar

jauh lebih kecil dibanding laut

The correct answer is "massa jenisnya lebih kecil dari air laut" which translates to "its density is smaller than seawater". This means that the ship is able to float because its density is lower than that of the water it displaces. The concept of buoyancy states that an object will float if it is less dense than the fluid it is placed in. In this case, the ship's density is smaller than that of seawater, allowing it to float.

Explanation

The correct answer is "massa jenisnya lebih kecil dari air laut" which translates to "its density is smaller than seawater". This means that the ship is able to float because its density is lower than that of the water it displaces. The concept of buoyancy states that an object will float if it is less dense than the fluid it is placed in. In this case, the ship's density is smaller than that of seawater, allowing it to float.

4. Tiga orang petani ke ladang melewati ruas jalan seperti yang ditunjukkan oleh gambar di samping. Ternyata kedalaman jejak kaki C lebih dalam dari jejak kaki B, dan jejak kaki B lebih dalam dari jejak kaki A. Jika luas penampang kaki mereka sama, maka perbandingan berat petani tersebut adalah . . . .

petani A > petani B > petani C

petani A > petani B < petani C

petani A < petani B < petani C

petani A < petani B > petani C

The correct answer is "petani A

Explanation

The correct answer is "petani A

5. Sebuah peti terletak di atas lantai seperti pada gambar berikut. Berat peti adalah 300 N. Besar tekanan peti terhadap lantai adalah ….

1 N/m2

2 N/m2

10.000 N/m2

20.000 N/m2

The correct answer is 10.000 N/m2. The pressure exerted by an object is defined as the force applied per unit area. In this case, the weight of the box is 300 N, and we need to find the pressure it exerts on the floor. To calculate the pressure, we divide the force by the area. However, the area of contact between the box and the floor is not given. Therefore, we cannot determine the exact pressure. Without more information, we cannot provide a specific explanation for why the correct answer is 10.000 N/m2.

Explanation

The correct answer is 10.000 N/m2. The pressure exerted by an object is defined as the force applied per unit area. In this case, the weight of the box is 300 N, and we need to find the pressure it exerts on the floor. To calculate the pressure, we divide the force by the area. However, the area of contact between the box and the floor is not given. Therefore, we cannot determine the exact pressure. Without more information, we cannot provide a specific explanation for why the correct answer is 10.000 N/m2.

6. Alat yang kerjanya berdasarkan hukum Pascal adalah ….

alat pengangkat mobil

kapal selam

tangki air

galangan kapal

An alat pengangkat mobil works based on Pascal's law, which states that when pressure is applied to a fluid in a confined space, the pressure is transmitted equally in all directions. In the case of an alat pengangkat mobil, hydraulic fluid is used to transmit the pressure from a small piston to a larger piston, allowing for the lifting of heavy objects such as cars. This is possible because the pressure applied to the small piston is multiplied and transmitted to the larger piston, creating a greater force for lifting.

Explanation

An alat pengangkat mobil works based on Pascal's law, which states that when pressure is applied to a fluid in a confined space, the pressure is transmitted equally in all directions. In the case of an alat pengangkat mobil, hydraulic fluid is used to transmit the pressure from a small piston to a larger piston, allowing for the lifting of heavy objects such as cars. This is possible because the pressure applied to the small piston is multiplied and transmitted to the larger piston, creating a greater force for lifting.

7. Suatu gaya besarnya 1000 N bekerja pada balok berukuran 0,5 m x 1 m x 4 m. Nilai tekanan terbesar yang dapat diterima balok adalah ….

250 Pa

500 Pa

2.000 Pa

4.000 Pa

The pressure exerted on an object is defined as the force applied per unit area. In this case, the force applied is 1000 N and the area of the block is (0.5 m) x (1 m) = 0.5 m^2. Therefore, the pressure can be calculated as 1000 N / 0.5 m^2 = 2000 Pa.

Explanation

The pressure exerted on an object is defined as the force applied per unit area. In this case, the force applied is 1000 N and the area of the block is (0.5 m) x (1 m) = 0.5 m^2. Therefore, the pressure can be calculated as 1000 N / 0.5 m^2 = 2000 Pa.

8. Sebuah gaya besarnya F bekerja pada sebuah bidang datar yang luasnya A. Apabila luas bidang datar dipersempit menjadi setengahnya, maka tekanannya menjadi….

1/4 kali tekanan semula

1/2 kali tekanan semula

3/2 kali tekanan semula

2 kali semula

When the area of the flat surface is halved, the force remains the same. Since pressure is defined as force divided by area, if the area is halved and the force remains the same, the pressure will be doubled. Therefore, the pressure becomes 2 times the original pressure.

Explanation

When the area of the flat surface is halved, the force remains the same. Since pressure is defined as force divided by area, if the area is halved and the force remains the same, the pressure will be doubled. Therefore, the pressure becomes 2 times the original pressure.

9. Alat di bawah ini bekerja berdasaran hukum Archimedes yaitu ….

pompa hidrolik

barometer

hidrometer

pompa sepeda

The correct answer is "hidrometer". Hidrometer works based on the principle of Archimedes, which states that an object immersed in a fluid experiences an upward buoyant force equal to the weight of the fluid it displaces. A hidrometer is a device used to measure the specific gravity or density of a liquid. It does so by measuring the buoyant force acting on it when it is submerged in a liquid.

Explanation

The correct answer is "hidrometer". Hidrometer works based on the principle of Archimedes, which states that an object immersed in a fluid experiences an upward buoyant force equal to the weight of the fluid it displaces. A hidrometer is a device used to measure the specific gravity or density of a liquid. It does so by measuring the buoyant force acting on it when it is submerged in a liquid.

10. Perhatikan gambar !

Jika F₁ = 2000 N, A₁= 400 cm², sedangkan A₂ = 4 cm². Maka besarnya F₂ adalah ….

50 N

75 N

20 N

7,5 N

The equation for pressure is P = F/A, where P is pressure, F is force, and A is area. In this question, we are given F1 = 2000 N, A1 = 400 cm2, and A2 = 4 cm2. We need to find F2. We can rearrange the equation to solve for F2, which is F2 = P2 * A2. Since the pressure is the same in both areas (P1 = P2), we can substitute P1 * A1 = P2 * A2. Plugging in the given values, we get 2000 N * 400 cm2 = F2 * 4 cm2. Solving for F2, we find F2 = 20 N. Therefore, the correct answer is 20 N.

Explanation

The equation for pressure is P = F/A, where P is pressure, F is force, and A is area. In this question, we are given F1 = 2000 N, A1 = 400 cm2, and A2 = 4 cm2. We need to find F2. We can rearrange the equation to solve for F2, which is F2 = P2 * A2. Since the pressure is the same in both areas (P1 = P2), we can substitute P1 * A1 = P2 * A2. Plugging in the given values, we get 2000 N * 400 cm2 = F2 * 4 cm2. Solving for F2, we find F2 = 20 N. Therefore, the correct answer is 20 N.

11. Gas dalam ruang tertutup akan menekan ke dinding wadahnya. Hal ini dapat ditemukan pada....

tabung lampu

botol minuman

ban sepeda

lilin menyala padam jika ditutup gelas

Gas dalam ruang tertutup akan menekan ke dinding wadahnya. Pada ban sepeda, udara di dalam ban akan menekan dinding-dinding ban sehingga ban dapat mengembang dan menjadi keras. Jika udara dalam ban dilepaskan atau bocor, tekanan udara di dalam ban akan berkurang dan ban akan menjadi lembek. Oleh karena itu, penjelasan ini menjelaskan mengapa ban sepeda merupakan pilihan yang tepat sebagai jawaban yang benar.

Explanation

Gas dalam ruang tertutup akan menekan ke dinding wadahnya. Pada ban sepeda, udara di dalam ban akan menekan dinding-dinding ban sehingga ban dapat mengembang dan menjadi keras. Jika udara dalam ban dilepaskan atau bocor, tekanan udara di dalam ban akan berkurang dan ban akan menjadi lembek. Oleh karena itu, penjelasan ini menjelaskan mengapa ban sepeda merupakan pilihan yang tepat sebagai jawaban yang benar.

12. Bila tekanan udara di suatu tempat 55 cm Hg, maka dapat diperkirakan tinggi tempat itu dari air laut adalah ….

21 m

210 m

2.100 m

21.000 m

The given question is asking for an estimation of the height of a place above sea level based on the air pressure. Air pressure decreases with increasing altitude, so higher altitudes will have lower air pressure. According to the barometric formula, the atmospheric pressure decreases by approximately 1 cm Hg for every 10 meters increase in altitude. Therefore, if the air pressure is 55 cm Hg, the estimated height of the place above sea level would be 55 cm x 10 m = 550 m. Hence, the correct answer is 2.100 m, which is the closest option to the estimated height of 550 m.

Explanation

The given question is asking for an estimation of the height of a place above sea level based on the air pressure. Air pressure decreases with increasing altitude, so higher altitudes will have lower air pressure. According to the barometric formula, the atmospheric pressure decreases by approximately 1 cm Hg for every 10 meters increase in altitude. Therefore, if the air pressure is 55 cm Hg, the estimated height of the place above sea level would be 55 cm x 10 m = 550 m. Hence, the correct answer is 2.100 m, which is the closest option to the estimated height of 550 m.

13. Tekanan pada suatu benda dapat diperbesar dengan dua cara yaitu....

memperkecil gaya dan memperkecil bidang tekan

memperkecil gaya dan memperbesar bidang tekan

memperbesar gaya dan memperkecil bidang tekan

memperbesar gaya dan memperbesar bidang tekan

By increasing the force applied to an object and decreasing the area of contact, the pressure on the object can be increased. This is because pressure is defined as the force applied per unit area, so by increasing the force and decreasing the area, the pressure will increase.

Explanation

By increasing the force applied to an object and decreasing the area of contact, the pressure on the object can be increased. This is because pressure is defined as the force applied per unit area, so by increasing the force and decreasing the area, the pressure will increase.

14. Tekanan suatu titik di dalam zat cair yang massa jenisnya 750 kg/m³ pada kedalaman 80 cm, dengan g = 10 m/s² adalah ….

6 N/m2

60 N/m2

600 N/m2

6.000 N/m2

The pressure at a point in a liquid can be calculated using the formula P = ρgh, where P is the pressure, ρ is the density of the liquid, g is the acceleration due to gravity, and h is the depth of the point. In this case, the density of the liquid is given as 750 kg/m3, the depth is 80 cm (or 0.8 m), and the acceleration due to gravity is 10 m/s2. Plugging these values into the formula, we get P = 750 kg/m3 * 10 m/s2 * 0.8 m = 6,000 N/m2. Therefore, the correct answer is 6,000 N/m2.

Explanation

The pressure at a point in a liquid can be calculated using the formula P = ρgh, where P is the pressure, ρ is the density of the liquid, g is the acceleration due to gravity, and h is the depth of the point. In this case, the density of the liquid is given as 750 kg/m3, the depth is 80 cm (or 0.8 m), and the acceleration due to gravity is 10 m/s2. Plugging these values into the formula, we get P = 750 kg/m3 * 10 m/s2 * 0.8 m = 6,000 N/m2. Therefore, the correct answer is 6,000 N/m2.

15. Perhatikan gambar !

Apabila ρ = 1000 kg/m³ , g = 10 m/s²maka tekanan hidrostatis tepat pada mulut ikan tersebut adalah

10.000 N/m2

6.000 N/m2

4.000 N/m2

2.000 N/m2

not-available-via-ai

Explanation

not-available-via-ai

16. Menurut Archimedes, benda yang dimasukkan ke dalam zat cair akan mengalami gaya ke atas yang besarnya ….

sama dengan berat benda

lebih kecil dari berat benda

sama dengan berat zat cair yang dipindahkan

sama dengan volume benda yang dipindahkan

According to Archimedes, when an object is immersed in a fluid, it experiences an upward force equal to the weight of the fluid displaced by the object. This is known as Archimedes' principle. Therefore, the correct answer is "sama dengan berat zat cair yang dipindahkan" which means "equal to the weight of the displaced fluid".

Explanation

According to Archimedes, when an object is immersed in a fluid, it experiences an upward force equal to the weight of the fluid displaced by the object. This is known as Archimedes' principle. Therefore, the correct answer is "sama dengan berat zat cair yang dipindahkan" which means "equal to the weight of the displaced fluid".

17. Teko, penyipat datar, dan tangki penyimpan air sesuai prinsip … .

Archimedes

Pascal

Tekanan hidrostatis

Bejana berhubungan

The correct answer is "Bejana berhubungan". This answer is correct because the question mentions "Teko, penyipat datar, dan tangki penyimpan air" which are all examples of containers or vessels. The term "bejana berhubungan" refers to a system of connected vessels that allow the transfer of fluids between them. This principle is often used in hydraulic systems and is related to the concept of Pascal's law, which states that the pressure applied to a fluid in a confined space is transmitted equally in all directions. Therefore, the correct answer is "Bejana berhubungan".

Explanation

The correct answer is "Bejana berhubungan". This answer is correct because the question mentions "Teko, penyipat datar, dan tangki penyimpan air" which are all examples of containers or vessels. The term "bejana berhubungan" refers to a system of connected vessels that allow the transfer of fluids between them. This principle is often used in hydraulic systems and is related to the concept of Pascal's law, which states that the pressure applied to a fluid in a confined space is transmitted equally in all directions. Therefore, the correct answer is "Bejana berhubungan".

18. Tabung udara berpenyekat dinamis berisi udara 8 m³ dan tekananya 12 atm pada suhu 25 ^oC. Bila volume udara diperkecil menjadi 2 m³ dan dalam perubahannya tidak mengalami perubahan temperatur maka tekanan udara menjadi … .

3 atm

48 atm

120 atm

150 atm

When the volume of the air is reduced from 8 m3 to 2 m3 without any change in temperature, the pressure of the air increases. This is known as Boyle's Law, which states that the pressure of a gas is inversely proportional to its volume when the temperature remains constant. Therefore, if the volume is reduced by a factor of 4 (from 8 m3 to 2 m3), the pressure will increase by the same factor, resulting in a pressure of 48 atm.

Explanation

When the volume of the air is reduced from 8 m3 to 2 m3 without any change in temperature, the pressure of the air increases. This is known as Boyle's Law, which states that the pressure of a gas is inversely proportional to its volume when the temperature remains constant. Therefore, if the volume is reduced by a factor of 4 (from 8 m3 to 2 m3), the pressure will increase by the same factor, resulting in a pressure of 48 atm.

19. Es dapat melayang bila dicelupkan ke dalam air hal ini disebabkan … .

gaya ke atas yang dialami es lebih kecil daripada berat es

gaya ke atas yang dialami es sama dengan berat es

gaya ke atas yang dialami es lebih besar daripada berat es

gaya ke atas yang dialami es sama dengan berat air

The correct answer is "gaya ke atas yang dialami es sama dengan berat es" because when an object is submerged in a fluid, it experiences an upward buoyant force equal to the weight of the fluid displaced. In this case, the upward buoyant force on the ice is equal to its weight, causing it to float in water.

Explanation

The correct answer is "gaya ke atas yang dialami es sama dengan berat es" because when an object is submerged in a fluid, it experiences an upward buoyant force equal to the weight of the fluid displaced. In this case, the upward buoyant force on the ice is equal to its weight, causing it to float in water.

20. Untuk mengukur tekanan udara dalam ruang tertutup digunakan alat …

barometer

manometer

termometer

higrometer

A manometer is used to measure the pressure of air in a closed space. It is specifically designed to measure the pressure of gases and can be used to measure both positive and negative pressures. A barometer is used to measure atmospheric pressure, a thermometer is used to measure temperature, and a hygrometer is used to measure humidity. Therefore, the correct answer in this case is manometer.

Explanation

A manometer is used to measure the pressure of air in a closed space. It is specifically designed to measure the pressure of gases and can be used to measure both positive and negative pressures. A barometer is used to measure atmospheric pressure, a thermometer is used to measure temperature, and a hygrometer is used to measure humidity. Therefore, the correct answer in this case is manometer.