The two main function of a transistor is to amplify or switch electronic signals. The switch is two options: on / off. The amplification function is a change in voltage.
A parachute increases air friction, thus reducing falling speed.
Indeed, the air friction is roughly proportional to the surface of the object falling down; the parachute tremendously increases that surface.
Answer:
The time is 
Explanation:
Given that,
Capacitor = 120 μF
Voltage = 150 V
Resistance = 1.8 kΩ
Current = 50 mA
We need to calculate the discharge current
Using formula of discharge current

Put the value into the formula


We need to calculate the time
Using formula of current

Put the value into the formula





Hence, The time is 
The part that moves are called anti-nodes. The stationary pars are nodes
9.8m per seccond is the speed of gravity if you drop something like a ball from a tower