Four movers pick up boxes. Each box has a different mass, and each mover applies a different amount of force to lift the box. Which box will have the greatest acceleration?

Question

A. A 20 kg box lifted with 60 N of force
B. A 20 kg box lifted with 40 N of force
C. A 10 kg box lifted with 40 N of force
D. A 10 kg box lifted with 60 N of force

Answer 1

The acceleration of an object can be calculated using Newton's second law of motion, which states that force is equal to mass times acceleration (F=ma).

Let's calculate the acceleration for each option:

A. A = F/m = 60N / 20kg = 3 m/s²
B. A = F/m = 40N / 20kg = 2 m/s²
C. A = F/m = 40N / 10kg = 4 m/s²
D. A = F/m = 60N / 10kg = 6 m/s²

Therefore, the 10 kg box lifted with 60 N of force (option D) will have the greatest acceleration with 6 m/s².

Answer 2

A baseball has a mass of 145g. A pitcher throws the baseball so that it accelerates at a rate of 80 m/s². How much force did the pitcher apply to the baseball.
A. 65 N
B. 11.6 N
C. 1.8 N
D. 0.6 N

Answer 3

To calculate the force applied by the pitcher to the baseball, we can use Newton's second law of motion (F=ma), where F is the force, m is the mass, and a is the acceleration.

First, we need to convert the mass of the baseball from grams to kilograms:
Mass of baseball = 145g = 0.145 kg

Now we can calculate the force:
F = m * a = 0.145kg * 80 m/s² = 11.6 N.

Therefore, the pitcher applied a force of 11.6 N (option B) to the baseball.

Answer 4

Which situation describes a negative acceleration?
A. A diver jumping off a diving board and falling to the swimming pool below
B. A bicycle increasing its velocity as the rider pedals harder
C. A swimmer moving at a constant velocity
D. A runner slowing down at the end of a race

Answer 5

A runner slowing down at the end of a race (option D) describes a negative acceleration.