Answer:
c. 1600J
Explanation:
The loss in potential energy of the boy is given by:

where
m = 40 kg is the mass of the boy
g = 9.8 m/s^2 is the acceleration of gravity
is the total change in the height of the boy (4 metres + 2 cm due to the compression of the spring)
Substituting, we find

Solution: From the given question, we shall find the vector quantity among the
(A) Time , (B) Velocity, (C) Distance , (D) Speed
Concept: <u>Vector Quantity: </u>All those physical quantities which have magnitude as well as specific directions, are called Vector Quantities.
Here, Time, Distance and Speed have only magnitude but have no directions so they will be scalar quantities.
Now, <u>Velocity:</u> It is defined as the change in displacement per unit time. Since the change in the displacement will be in particular direction only. Hence, velocity will be the vector quantity.
Hence, the option (B) Velocity will be the correct option.
Answer:
Resulting Change in the Magnetic Flux 
Explanation:
Thanks!
Answer:
it increases-
Explanation:
When the mass of a rocket decreases as it burns through its fuel and the force ( thrust) is constant then by newtons second law of motion
F= ma here F is constant this means that ma= constant
⇒ m= F /a this implies that mass is inversely proportional to acceleration.
its means when the mass decreases the acceleration must increase. hence the acceleration increases