An object cannot remain at rest unless which of the following holds? there are no forces at all exerted on it. there is only one force exerted on it. the net force exerted on it is constant and nonzero. the net force exerted on it is zero. if a block is moving to the left at a constant velocity, what can one conclude? the net force exerted on the block is directed to the left. the net force exerted on the block is zero. there must be no forces at all exerted on the block. there is exactly one force exerted on the block. a block of mass 2kg experiences a force of magnitude 4 newtons directed to the right. what can you say about the block's motion? it must be moving to the left. it could be moving to the left, moving to the right, or be instantaneously at rest. it must be moving to the right. it must be at rest. a block is being pulled along a horizontal frictionless surface by a constant horizontal force. the block must be moving with a constant nonzero acceleration. moving at constant velocity. moving with continuously increasing acceleration. continuously changing direction.

Explanation:

1. An object cannot remain at rest unless the net force exerted on it is zero. It is also known as the Newton's first law of motion. So, the correct option is (D).

2.  If a block is moving to the left at a constant velocity, that means the velocity is same. So, the change in velocity is zero that is acceleration is zero. So, the net force exerted on the block is zero.

3. Mass of the block, m = 2 kg

Force experienced by the block, F = 4 N (towards right)

Since, the force is acting towards right.. So, the block will accelerates towards rest at the rate of 2 m/s². So, It must be moving to the right is the correct option.

4. A block is being pulled along a horizontal friction less surface by a constant horizontal force. Since, the force is constant, the acceleration will be constant. So, the block must be moving with a constant nonzero acceleration is the correct option.

Hence, this is the required solution.

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beta is electron from nucleus

something from nucleus has changed, but charge must be same for cons of charge