onsider two projectiles that can be shot upward by spring guns. Object A is made of solid aluminum and has a mass of 50 grams. Object B is made of cast iron and has a mass of 200 grams. For this problem, you may take the gravitational field strength to be g = 10 N/kg. show answer Correct Answer 14% Part (a) Masses A and B are both shot straight upward at the same time. Mass A is shot with a speed of 2 m/s and mass B with a speed of 1 m/s. Which one hits the ground first?

B

Explanation:

From Newton's law of motion, we have:

V^2 = U^2 + 2gH

Where V and U are final and initial velocity respectively.

H is the height.

For the object to have a sustain a maximum height it means the final velocity of the object is zero.

By computing the height of the object sustain by A, we have:

0^2 = 2^2 - 2*10*H

0 = 4 - 20H

4 = 20H;

H = 0.2m

For object B we have;

0^2 = 1^2 - 2*10*H

0 = 1 - 20H

H = 1/20 = 0.05m

From computing the height sustain by both objects, we see object B is projected at a shorter height into atmosphere than A.

Hence object B will return to the ground first.