Answer:

Explanation:
Given that

We know that acceleration a given as




We know that



So the magnitude of force F

In ocean waves, water particles move with mechanical energy and energy moves with gravity
Not sure but hope it helps!
<em>Choice-A </em>is a true statement. The string holding the ball in orbit is a contact force, whereas gravity is a non-contact force.
Choice-C is half-true. The string keeps the distance between the bodies constant, but gravity doesn't "MAKE" the distance vary.
Answer:

Explanation:
It is given that,
Speed of the projectile is 0.5 v. Let h is the height above the ground. Using the first equation of motion to find it.


Initial speed of the projectile is v and final speed is 0.5 v.


g is the acceleration due to gravity
Let h is the height above the ground. Using the second equation of motion as :



So, the height of the projectile above the ground is
. Hence, this is the required solution.
Potential Energy = mgh ,
mass = 1.4 kg, g ≈ 10 m/s², h = 0.8m
Potential Energy = mgh = 1.4 * 10 * 0.8 = 11.2 N
Potential Energy added = 11.2 N