Answer:
The same
Explanation:
The change in momentum of each cart is equal to the impulse given by the force applied on the cart:

where
F is the force applied
is the time during which the force is applied
The force applied to both carts (F) is the same, as well as the time (
). This means that the change in momentum,
, is the same for both carts. But both carts start from rest (momentum = 0): this means that at the end, both carts will have exactly same momentum.
Answer:
v = 12.12 m/s
Explanation:
Given that,
The mass of the cart, m = 75 kg
The roller coaster begins 15 m above the ground.
We need to find the velocity of the cart halfway to the ground. Let the velocity be v. Using the conservation of energy at this position, h = 15/2 = 7.5 m

So, the velocity of the cart is 12.12 m/s.
Answer:
1. The current will drop to half of its original value.
Explanation:
The problem can be solved by using Ohm's law:

where
V is the voltage across the circuit
R is the resistance of the circuit
I is the current
We can rewrite it as

In this problem, we have:
- the resistance of the circuit remains the same: R' = R
- the voltage is decreased to half of its original value: 
So, the new current will be

so, the current will drop to half of its original value.