2,3 / 2,4 Reading Quiz - Work Done, PE Ke, Power, Circular Motion

1. 20N pushes a box 6m in 3 seconds. What is the work done by the force?

360J

120J

60J

18J

Explanation

2. What is the average power used in moving an object with 20N for a distance of 6m in 3seconds?

3.33W

2W

6.66W

40W

https://dl.dropboxusercontent.com/u/15735665/DIPLOMA/CH%20quiz%20images/MC%20images/2-4q2.JPG

Explanation

https://dl.dropboxusercontent.com/u/15735665/DIPLOMA/CH%20quiz%20images/MC%20images/2-4q2.JPG

3. What aspect of a force distance graph give you the work done?

The gradient,

The area

Half the area

The second derivative

The work done is determined by the area under the force-distance graph. This is because work is defined as the product of force and displacement, and the area under the graph represents the product of force and distance. Therefore, the greater the area under the graph, the greater the work done. The gradient of the graph, on the other hand, represents the force applied, not the work done. The second derivative is not relevant to determining the work done.

Explanation

The work done is determined by the area under the force-distance graph. This is because work is defined as the product of force and displacement, and the area under the graph represents the product of force and distance. Therefore, the greater the area under the graph, the greater the work done. The gradient of the graph, on the other hand, represents the force applied, not the work done. The second derivative is not relevant to determining the work done.

4. A 2Kg mass is given 100J of KE. How high will it reach if it is thrown vertically upwards?

2.5m

5m

25m

50m

KE turns into mgh
KE=mgh
100 =2x10xh
h=5m

Explanation

KE turns into mgh
KE=mgh
100 =2x10xh
h=5m

5. 2Kg mass is thrown with a velocity of 5m/s. What is its KE?

5J

10J

25J

50J

https://dl.dropboxusercontent.com/u/15735665/DIPLOMA/CH%20quiz%20images/MC%20images/2-4%20q4.JPG

Explanation

https://dl.dropboxusercontent.com/u/15735665/DIPLOMA/CH%20quiz%20images/MC%20images/2-4%20q4.JPG

6. A speed boat is able to travel with a maximum velocity of 20m/s. The power rating of the engine is 2000W. What is the sum of the frictional forces on the boat?

40,000 N

200 N

100 N

50 N

Explanation

7. What is an elastic collision?

Where mass is conserved

Where energy is conserved

Where kinetic energy is conserved

Where potential energy is conserved

An elastic collision is a type of collision in which kinetic energy is conserved. This means that the total kinetic energy of the system before the collision is equal to the total kinetic energy after the collision. In an elastic collision, there is no loss of kinetic energy due to friction or deformation of the objects involved. Instead, the objects bounce off each other without any loss of energy, resulting in a conservation of kinetic energy.

Explanation

An elastic collision is a type of collision in which kinetic energy is conserved. This means that the total kinetic energy of the system before the collision is equal to the total kinetic energy after the collision. In an elastic collision, there is no loss of kinetic energy due to friction or deformation of the objects involved. Instead, the objects bounce off each other without any loss of energy, resulting in a conservation of kinetic energy.