Physics Quiz on Ch. 3 Linear Motion

If a car accelerates from rest at 3 meters per second per second, its speed 4 second later will be about

12 m/s.

Disregarding air drag, how fast must you toss a ball straight up in order for it to take 3 seconds to return to the level from which you tossed it?

15 m/s.

If a car increases its velocity from zero to 60 km/h in 30 seconds, its acceleration is

2 km/h/s

Someone standing at the edge of a cliff (50 m high) throws one ball straight up and another ball straight down at the same initial speed 10 m/s. Neglecting air resistance, what is the time difference between the balls to hit the ground?

2 s.

Can an object be moving when its acceleration is zero?

Yes.

A ball is thrown upwards and caught when it comes back down. Neglecting air resistance, the speed with which it is caught is always

the same as the speed it had when thrown upwards.

An object falls freely from rest on a plant where the acceleration due to gravity is 6 meters per second squared. After 4 seconds, the object will have a speed of

24 m/s.

A rock is dropped into a river from a very high bridge at time t = 0 second. At the time t = 2 second, another rock is dropped, and t= 3 second dropped 3rd rock. What is the distance between 1st and 2nd rock when dropping the 3rd one?

40 m.

A car accelerates from 25 km/h to 75 km/h in 10 s. What is its acceleration during this time?

5 km/h/s.

If a projectile is fired straight up of 25 m/s, the total time to return to its starting position is about

5 seconds.

Four seconds after starting from rest, an object falling freely will travel a distance of

80 m.

A ball is thrown upwards. Neglecting air resistance, what initial upward speed does the ball need to remain in the air for a total time of 10 seconds?

about 30 m/s.

It takes 4 seconds for a stone to fall to the bottom of a mine shaft. How deep is the shaft?

about 80 m.

Disregarding air resistance, a bowling ball and a baseball fall down the roof with constant

acceleration.

A hockey puck is set in motion across a frozen pond. If the net force on puck is zero, the puck slides

at constant velocity.

What is acceleration?

change position over time change of velocity over time both of them

What is average velocity?

displacement over time.

While an object near the Earth's surface is in free fall, its

velocity increases.

A man leans over the edge of a cliff and throws a rock upward at 14.7 m/s. Neglecting air resistance, 1.5 second later the rock's speed is

zero.