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

Given: Mass m = 44 Kg; Velocity v = 10 m/s
Required: Kinetic energy K.E = ?
Formula: K.E = 1/2 mv²
K.E 1/2 (44 Kg)(10 m/s)²
K.E = 2,200 Kg.m²/s²
K.E = 2,200 J Answer is A
B.adding carpet and fabric wall covering to absorb sound
Mechanical digestion is chewing, and chemical digestion is the saliva in your mouth breaking down food.
Answer:A solenoid is a simple electromagnetic device consisting of a coiled electric wire, wrapped in a 3D circular pattern. When electric current is passed through the wire, the solenoid acts like a magnet with N and S poles at the ends of the coil.
When a ferromagnetic material rod is permanently placed inside the solenoid, the metal greatly increases the magnetic effect and becomes a permanent electromagnet. Moreover, it can also be used as an electrical switch by drawing in or pushing out a ferromagnetic material like an iron rod. Depending on the directions of the rod and the electrical current the switching action takes place.
Given figure represents the solenoid as electromagnet and the switching action.
Explanation: