Chapter 2 Review Grade-9 Jan 11, 2021

• Science
• Secondary Education

SCIENCE 

GRADE-9

JAN 11, 2021

Ms.FAMIN

LETS BEGIN

McGRAW hill Recall activity 

OBJECTIVES 

Differentiate contact and non contact forces 

state Universal law of gravitation 

state Newton's laws of motion

You push a book sitting on a desk with a force of 5N, but the book does not move. what is its static friction?

1. 0 N
2. Between 0N and 5N
3. 5 N
4. Greater than 5N

Which is always a contact force?

1. electric
2. friction
3. gravity
4. magnetic

According to law of gravitation, gravity increases with which conditions?

1. mass increases, distance decreases
2. mass decreases, distance decreases
3. mass decreases, distance increases
4. none of the above

Explain why feather falls slowly rather than fast

INERTIA 

What causes an object in motion to remain in motion?

1. friction
2. gravity
3. velocity
4. inertia

Find the net force

1. 8 N, right
2. 2 N, left
3. 2 N, right
4. 8 N, left

What happens when unbalanced forces act on an object at rest?

1. the object remain at rest
2. the object begins moving in an unpredictable direction
3. the object begins moving in the direction of the net force
4. the object begins moving opposite to the direction of net force

This equation goes with which law?

1. Newton's first law
2. netwon's second law
3. newton's third law
4. none of these

A cat pushes a 0.25 kg toy with net force 8 N, what is the acceleration of the ball?

1. 2 m/s^2
2. 16 m/s^2
3. 4 m/s^2
4. 32 m/s^2

interpret

When these marbles collide, what force is experienced by each marble?

1. The force on each is 0.1 N to the right.
2. The force on each is 0.1 in opposite directions.
3. The force on each is 0.1 N to the left
4. The force on the smaller marble is larger than the force on the larger marble

What is a measure of how hard it is to stop a moving object?

1. momentum
2. gravity
3. friction
4. velocity

back to objectives

Differentiate contact and non contact forces

state Universal law of gravitation

state Newton's laws of motion

How well did you understand laws of motion?