1.
The average speed of a horse that gallops a distance of 10 kilometers in a time of 30 minutes is ______.express answers in kph. example: 90 kph
Correct Answer
20 kph
20kph
20.0 kph
20.0kph
Explanation
convert 30 min to hours then you have 0.5 hr.
10km/0.5hr gives 20 kph
2.
As an object freely falls, its
Correct Answer
A. Velocity increases
Explanation
when an object in undergoing freefall, it is under the influence of the Earth's gravitational pull causing it to accelerate uniformly and thus increasing its velocity as it falls =]
3.
If an object falls with constant acceleration, the velocity of the object must
Correct Answer
B. Continually change by the same amount each second.
Explanation
acceleration due to gravity is 'almost' constant at the surface of the earth. so constant acceleration means constant increase in velocity =]
4.
Drop a rock from a 5-m height and it accelerates at 10 m/s^{2} and strikes the ground 1 second later. Drop the same rock from a height of 10 m and its acceleration of fall is
Correct Answer
C. The same
Explanation
acceleration due to gravity is 'almost' constant at the surface of the earth. so raising or lowering the height of releasing an object would have no significant effect. =]
5.
At one instant an object in freefall is moving downward at 50 m/s. One second later its speed is about
Correct Answer
D. 60 m/s
Explanation
common sense na lang ang paganahin naten dito.
the rock is in freefall therefore it a = 10 m/s^2
after falling for 1 second, it gains a speed of 10 m/s
6.
At one instant an object in freefall is moving upward at 50 m/s. One second later its speed is about
Correct Answer
E. 40 m/s
Explanation
common sense na lang ang paganahin naten dito.
the rock is in freefall therefore it a = 10 m/s^2
after moving upward for 1 second, it decelerates, thus reducing its speed by about 10 m/s
7.
While a car travels aroud a circular track at constant speed its
Correct Answer
D. None of these
Explanation
While a car travels around a circular track at a constant speed, its velocity is not zero because velocity is a vector quantity that includes both speed and direction. The car is continuously changing its direction as it moves along the circular track, so its velocity is not zero. Additionally, the car's acceleration is also not zero because acceleration is the rate of change of velocity. Even though the car is moving at a constant speed, it is constantly changing its direction, which means it is experiencing acceleration. Therefore, the correct answer is none of these.
8.
An apple falls from a tree and hits the ground 5 meters below. It hits the ground with a speed of about
Correct Answer
B. 10 m/s
Explanation
The apple falls from a height of 5 meters, and we know that the acceleration due to gravity is approximately 9.8 m/s^2. Using the equation v^2 = u^2 + 2as, where v is the final velocity, u is the initial velocity (which is 0 in this case), a is the acceleration, and s is the distance fallen, we can calculate the final velocity. Plugging in the values, we get v^2 = 0 + 2(9.8)(5), which simplifies to v^2 = 98. Solving for v gives us v â‰ˆ âˆš98 â‰ˆ 9.9 m/s, which is closest to 10 m/s.
9.
Motion that is under the influence of gravity alone.
Correct Answer
free fall
Explanation
Free fall refers to the motion of an object when it is only influenced by gravity, with no other forces acting upon it. In free fall, the object experiences a constant acceleration due to gravity, causing it to fall towards the Earth without any resistance or external forces. This motion is commonly observed when an object is dropped from a height or when a skydiver jumps out of a plane. During free fall, the object's velocity increases continuously, leading to a rapid increase in its speed as it falls downwards.
10.
When a rock thrown straight upwards gets to the exact top of its path, its
Correct Answer
B. Velocity is zero and its acceleration is about 10 m/s^2
11.
If a projectile is fired straight up at a speed of 30 m/s, the total time to return to its starting position is about
Correct Answer
D. 6 seconds
Explanation
When a projectile is fired straight up, it will reach its highest point and then fall back down due to gravity. The time it takes to reach the highest point is equal to the time it takes to fall back down to its starting position. The total time can be calculated by dividing the total distance traveled by the projectile by its average speed. Since the projectile is fired straight up, the total distance traveled is twice the distance from the starting position to the highest point. Therefore, the total time to return to its starting position is longer than the time it takes to reach the highest point. Given that the initial speed is 30 m/s, it will take approximately 6 seconds for the projectile to return to its starting position.
12.
Uniformly accelerated motion that is a combination of horizontal and vertical motion that is independent of one another.
Correct Answer
Projectile motion
parabolic motion
Explanation
nasa notes iyan. tingin-tingin na lang.
13.
It is the path followed by a projectile thrown at an angle.
Correct Answer
trajectory
Explanation
nasa notes iyan. tingin-tingin na lang.
14.
A bullet is dropped from the top of the Empire State Building while another is fired downward from the same location. Neglecting air resistance, the acceleration
Correct Answer
C. Each bullet is 9.8 m/s^2
Explanation
free fall. acceleration due to free fall for any of the bullets is the same, 9.8 m/s^2
ang nagsagot ng D ay may minus. seriously =]
15.
Which two graphs best represent the motion of an object falling freely from rest near the Earth's surface?
Correct Answer
A. Set 1
Explanation
Set 1 na ang pinakamalapit. As the object falls, its speed increases and its acceleration remains at a constant
9.8 m/s^2
16.
Which graph best represents the motion of a block accelerating uniformly down an inclined plane?
Correct Answer
D. (4)
Explanation
the d vs t graph for an object accelerating uniformly will look like that. check notes. =]