Topic 7: Newton's First Law

Which of the following best describes Newton's First Law of Motion, or the Law of Inertia?

An object in motion stays in motion with the same speed and direction unless acted upon by an unbalanced force.

Objects naturally come to rest without any unbalanced forces acting on them.

False

What is true about the forces acting on an object at rest?

The net force acting on the object is zero

What is true about the forces acting on an object moving at constant velocity?

The net force acting on the object is zero

The acceleration due to gravity on Jupiter is approximately 24.8 m/s². What is the weight of a person whose mass is 70 kg on Jupiter?

1736 N

What is the net force on the following system?

70 N to the right

What is the acceleration of the following system?

10 m/s^2 to the right

You are pushing a crate rightwards with a mass of 10 kg with a force of 150 N. The surface is rough, and the frictional force has a magnitude of 100 N. what is the net force and acceleration on the mass?

Rightwards, 50 N, 5 ms^-2

You stand on a scale that rests on the floor of an elevator that is accelerating upward. What is the relationship between the force due to gravity (mg) and the normal force (N) exerted by the scale?

Normal force is larger than the weight

When you walk on the ground, your foot push against the ground, and the ground pushes back on you. (fill the blank) The force that makes you walk is exerted by -------------------------- on your foot

the ground.

A bug is hit by a car. Which one experiences a higher force?

Both will experience a same force

What are the forces acting on the following system?

The table is on a rough surface?

Weight downward, Normal Force upward, Push force to the left