A body of mass 1 kg moving on a smooth horizontal surface with velocity 5 m/s is to be brought to rest in 5 seconds. How much constant force is needed to be applied?Only one correct answerA.

To solve this problem, we can use Newton's second law of motion, which states that the force applied on an object is equal to the change in its momentum per unit time.

Step 1: Identify the initial and final velocities of the body. The initial velocity (u) is given as 5 m/s, and since the body is brought to rest, the final velocity (v) is 0 m/s.

Step 2: Identify the time taken for this change in velocity. The time (t) is given as 5 seconds.

Step 3: Calculate the change in velocity (which is also the acceleration in this case, since the time interval is considered). Acceleration (a) = (v - u) / t = (0 - 5) / 5 = -1 m/s². The negative sign indicates that this is a deceleration, or slowing down.

Step 4: Use Newton's second law to find the force. Force (F) = mass (m) * acceleration (a) = 1 kg * -1 m/s² = -1 N.

The negative sign indicates that the force is applied in the opposite direction to the motion of the body, which makes sense as we are trying to bring the body to rest.

So, the constant force needed to be applied is 1 N.