Answer:

Explanation:
Given that,
Initial speed of the cart, u = 0
Let F force is applied to the cart for time
after which the car has speed v. The force on an object is given by :
F = ma
m is the mass of the cart
We need to find the speed of second cart, if the same force is applied for the same time to a second cart with twice the mass. Force becomes,



So, the speed of second cart is half of the initial speed of first cart. So, the correct option is (b).
Answer:
The astronaut can throw the hammer in a direction away from the space station. While he is holding the hammer, the total momentum of the astronaut and hammer is 0 kg • m/s. According to the law of conservation of momentum, the total momentum after he throws the hammer must still be 0 kg • m/s. In order for momentum to be conserved, the astronaut will have to move in the opposite direction of the hammer, which will be toward the space station.
Explanation:
Answer:
Normal force
Explanation:
Normal force is the force that surfaces employ so that solid objects are disallowed from passing through each other.
In the image below, the focus lines are shown. The step can be done to bring the apple into focus is make the lens rounder. The correct option is A.
<h3>What is lens?</h3>
The lens is in spherical shape may be diverging or converging.
As light enters the eye, it is focused on the retina. Changing the pupil diameter, regulates the amount of light entering the eye. Changing lens shape will focus the light.
The changes in lens shape needed to maintain focus as the object distance changes.
Thus, the correct option is A.
Learn more about lens.
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