Revision of motion

On a velocity-time graph what does the gradient（斜率） symbolise(象征)?

• constant speed

• distance

• acceleration

• force

What is acceleration?

• how quickly distance is changing

• How quickly time is changing

• how quickly velocity is changing

What's the unit of acceleration?(2 correct answer)

• m

• m/s

What is weight caused by?

• mass

• constant force

• accelration

• gravity

What is Newton's first law?

• action force and reaction force

• balanced force means no change in velocity

• object acted by unbalanced force will move in constant speed

Give the equation relating force, mass and acceleration

• a=mF 

Which ones of these are vector quantities?

• distance

• force

• momentum

• acceleration

Give the equation relating momentum, velocity and mass

What's the unit of momentum?

What causes changes in momentum?

• distance

• time

• force

• constant speed