Answer:
0.304 m/s2
Explanation:
If the first child is pushing with a force of 69N to the right and the 2nd child is pushing with a force of 91N to the left. Then the net pushing force is 91 - 69 = 22 N to the left. Subtracted by 15N friction force then the system of interest is subjected to F = 7 N net force tot he left.
We can use Newton's 2nd law to calculate the net acceleration of the system

Answer:
(a) 
(b) 
(c) 
Solution:
As per the question:
Mass of Earth, 
Mass of Moon, 
Mass of Sun, 
Distance between the earth and the moon, 
Distance between the earth and the sun, 
Distance between the sun and the moon, 
Now,
We know that the gravitational force between two bodies of mass m and m' separated by a distance 'r' is given y:
(1)
Now,
(a) The force exerted by the Sun on the Moon is given by eqn (1):



(b) The force exerted by the Earth on the Moon is given by eqn (1):



(c) The force exerted by the Sun on the Earth is given by eqn (1):



Answer:
The correct option is:
B) Kinetic Energy
Explanation:
We know that if a body is placed at a certain height, it possesses Potential Energy, which is represented by 'mgh'. In this case, when the skydiver is present in the plane, before jumping, he has potential energy as he is at height 'h'.
As Kinetic energy is given as '(1/2)mv²' dependent on velocity of the object, when the skydiver jumps of the plane, his height starts decreasing, which decreases his Potential Energy. As energy can neither be created or destroyed, but is converted to one form or another, all this Potential energy starts to convert into Kinetic energy. As Potential Energy decreases with distance, Kinetic energy increases. Hence, line B represents Kinetic Energy.