Chap 3&4 (Easy)

Two forces, 4 N and 6 N, act on an object in the same direction. If the mass of the object is 5 kg, what is its acceleration?

• • 2 m/s^2

• • 10 m/s^2

• • 24 m/s^2

If a ball's velocity doubles, what happens to its momentum?

• • It halves

• It doubles

• It quadruples

A 5 kg object is stationary. What is its momentum?

• • 0 kg·m/s

• 5 kg·m/s

• 50 kg·m/s

Two ice skaters push off each other. What happens to their total momentum?

• • It increases

• • It decreases

• It stays the same

Which collision obeys the conservation of momentum?

• • Elastic and inelastic collisions

• • Only elastic collisions

• • Only inelastic collisions

A force of 15 N creates a moment of 45 Nm. What is the distance from the pivot?

• • 3 m

• • 30 m

• • 0.3 m

Why is it easier to open a door by pushing at its edge rather than near its hinges?

• • The distance from the pivot is greater.

• • The force is less at the edge.

• • The torque is smaller at the edge.

A seesaw is balanced. What is true about the moments on either side?

• • They are unequal.

• • They are equal.

• • They are zero.

Which of the following systems is in equilibrium?

• • A suspended object at rest

• • A moving object

• • A rotating object

What does the principle of moments state?

• • The total clockwise moment equals the total anticlockwise moment.

• • The total force equals zero.

• • The total torque is negative.