### (b) change in velocity and time

The 2 measurements necessary for calculating average acceleration are

(a)instantaneous velocity & time (b) change in velocity and time (c) distance and speed (d) velocity and distance

### (a) 0

What is the acceleration of a car that maintains a constant velocity of 100 km/hr for 10 secs?

(a) 0 (b) 10 km/hr(s) (c) 10 m/hr(s) (d) 1000 km/hr(s)

### (c) 100 m/s

Ten seconds after starting from rest, an object falling freely downward on Earth will have a speed of about

(a) 10 m/s (b) 50 m/s (c) 100 m/s (d) more than 100 m/s

### (a) 10 km/hr

The average speed of a horse that gallops a distance of 10 km/hr in a time of 1 hour is

(a) 10 km/hr (b) 20 km/hr (c) 30 km/hr (d) more than 30 km/hr

### (e) Your direction is constantly changing

Suppose you are in a car going due east on a straight highway at a constant speed of 30 mph. Which of the following is NOT true?

(a) You and the car's distance is constantly changing

(b) Your speed is constant

(c) Your velocity is constant

(d) Your acceleration is 0 m/s/s

(e) Your direction is constantly changing

### (b) 20 m/s

If an object falling freely downward was somehow equipped with a speedometer on a planet where the acceleration due to gravity is 20 m/s/s, then its speed reading would increase each second by

(a) 10 m/s (b) 20 m/s (c) 30 m/s (d) 40 m/s (e) Depends on initial speed

### (b) 6 km/hr(s)

If a car increases its velocity from 0 to 60 km/hr in 10 seconds, its acceleration is

(a) 60 km/hr(s) (b) 6 km/hr(s) (c) 10 km/hr(s) (d) 3 km/hr(s) (e) 600 km/hr(s)

### (d) 6 m/s

If Aunt Milly gave you $2 each sec for 3 secs, you could count how much money you would accumulate. If a car accelerates from rest at 2 m/s/s what is the speed 3 seconds after the car starts moving?

(a) 2 m/s (b) 3 m/s (c) 4 m/s (d) 6 m/s (e) none

### (d) all of the above

One possible unit of speed is

(a) miles per hour

(b) meters per second

(c) yards per century

(d) all of the above

(e) none

### (d) all of the above

Average speed is

(a) a measure of how fast something is moving

(b) the distance covered per unit of time

(c) always measured in terms of a unit of distance divided by a unit of time

(d) all of the above

(e) none

### (b) average speed is 8 meters per second

An object travels 8 meters in the first second of travel, 8 meters again during the 2nd second of travel, and 8 meters again in the 3rd second. This means the object's

(a) location is constant

(b) average speed is 8 meters per second

(c) average acceleration is 8 meters per second per second

(d) average speed and average acceleration are both 0

(e) average speed and average acceleration can't be found

### (e) 10 m/s

Assuming the conditions of free-fall, how fast must you toss a ball straight up in order for ti to take 2 secs to return to the level from which you tossed it?

(a) 5 m/s (b) 20 m/s (c) 7.5 m/s (d) 15 m/s (e) 10 m/s

### (b) 60 m/s

At one instant an object in free fall is moving downward at 50 m/s. The acceleration due to gravity in free fall is 10 m/s/s. One second later its speed is about

(a) 100 m/s (b) 60 m/s (c) 50 m/s (d) 40 m/s (e) 55 m/s

### (e) all the above

Which of the following controls can change a car's velocity?

(a) the gas pedal (b) the brake pedal

(c) the steering wheel (d) both A and B (e) all of the above

### (a) instantaneous speed

When you look at the spedometer in a moving car, you can see the car's

(a) instantaneous speed (b) average speed (c) instantaneous acceleration (d) direction (e) distance traveled

### (d) 4

A car accelerates from rest for 5 seconds until it reaches a speed of 20 m/s.What is the car's acceleration in m/s/s?

(a) 1 (b) 2 (c) 3 (d) 4 (e) 5

### (a) with no change in velocity, there is no acceleration

A bird flies due east for 600 meters at a constant speed of 10 m/s. What is the bird's acceleration?

(a) with no change in velocity, there is no acceleration

(b) 60 m/s (c) 6 m/s/s (d) 60 m/s/s

(e) not enough information is given

### (a) the steering wheel

The part of the car that can change velocity without changing speed is

(a) the steering wheel (b) the brake (c) the gas pedal

(d) nonsense, it is impossible to change velocity without changing speed

### (a) velocity is 0 and its acceleration is about 10 m/s/s

When a rock thrown straight upward gets to the exact top of its path, its

(a) velocity is 0 and its acceleration is about 10 m/s/s

(b) velocity is about 10 m/s and its acceleration is 0

(c) velocity is about 10 m/s and its acceleration is about 10 m/s/s

(d) velocity is 0 and so is acceleration

(e) none