Force, Mass and Acceleration

Force, Mass and Acceleration

Multiple Choice

Jackson need 100 N force to lift a 10 kg box. The force needed for Jackson to lift 30 kg box is ____

• the same (100N)

• bigger (more than 100N)

• smaller (less than 100N)

• can't be determined

​Mass and Force

​The force needed to act on a heavier object is bigger.

​

The force needed to act on a lighter object is smaller.

Multiple Choice

Mark likes to ride a bicycle. When he starts cycling, he applies 500 N of force. After 5 seconds, the bicycle's speed is 20 m/s.

If he wants his bicycle speed to be 50 m/s after 5 seconds, how much force needed?

• 500 N

• more than 500 N

•  than 500 N

• can't be determinded

​Acceleration and Force

Bigger force needed to make an object accelerate more.

​

Smaller force needed to make an object accelerate less.

​

​No force needed to make an object move at constant speed.

Multiple Choice

The correct formula to find force is

• $$force\ =\frac{mass}{acceleration}$$  

• $$Force=mass+acceleration$$  

• $$Force\ =\ mass\times acceleration$$  

• $$Force=\frac{acceleration}{mass}$$  

​Force formula

Multiple Choice

How to find mass?

• $$mass\ =\ force\ -\ acceleration$$  

• $$mass\ =force\times acceleration$$  

• $$mass=\frac{force}{acceleration}$$  

• $$mass=\frac{acceleration}{force}$$  

Multiple Choice

How to find acceleration?

• $$acceleration\ =\ force\ -\ mass$$  

• $$acceleration\ =force\times mass$$  

• $$acceleration=\frac{force}{mass}$$  

• $$acceleration=\frac{mass}{force}$$  

Multiple Choice

How much force is needed to accelerate a 66 kg skier at 2 m/s2?

• 132 N

• 33 N

• 64 N

• 68 N

Multiple Choice

What is the acceleration of a 50 kg object pushed with a force of 500 N?

• 25000 N/kg

• 550 N/kg

• 450 N/kg

• 10 N/kg

Multiple Choice

A 50 kg skater pushed by a friend accelerates 5 N/kg. How much force did the friend apply?

• 250 N

• 55 N

• 0.1 N

• 10 N

Multiple Choice

A force of 250 N is applied to an object that accelerates at a rate of 5 N/kg. What is the mass of the object?

• 50 kg

• 12

• 2

• 0.5 kg