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Which of these is an example of applying Newton's Second Law to calculate acceleration?

A person feels pushed backward when a car accelerates.

A car accelerates at 2 m/s² when a force of 4000 N is applied to it.

A car moves at constant velocity.

A rocket gains speed due to expelled gases.

What is the net force required to accelerate a 1000 kg car at 2 m/s²?

2000 N.

1500 N.

1000 N.

500 N.

Which of the following is an example of applying Newton's Third Law in a spacecraft?

A spacecraft accelerating due to expelled fuel.

A spacecraft gaining momentum in orbit.

A spacecraft moving in the opposite direction of the force applied.

A spacecraft traveling at constant speed in space.

In the figure, a shop keeper pulls a bag of rice of mass 50 kg along a rough horizontal floor, against a frictional force of 20N.

He applies a force of 100N on an inextensible string, inclined at an angle of 60° to the horizontal.

The acceleration of the bag is:

2 ms⁻².

0.3 ms⁻².

0.6 ms⁻².

6 ms⁻².

The force of 10 N is applied to a 2 kg object at rest. What will be the object's velocity after 5 seconds?

20 m/s.

10 m/s.

5 m/s.

2 m/s.