Answer:
v = 29.4m/s
Explanation:
Since the ball is dropped at rest,
u = 0m/s
a = 9.81m/s²
Using
v = u + at
After 3 seconds,
v = 0 + (9.81)(3)
v = 29.4m/s
Probably for the umbilical cord that connects babies (from their early stages in the womb to their removal) to their mothers. The cord is cut, forming the belly button. This is analogous to astronauts in space.
The relationship between frequency and wavelength for an electromagnetic wave is

where
f is the frequency

is the wavelength

is the speed of light.
For the light in our problem, the frequency is

, so its wavelength is (re-arranging the previous formula)
Answer:

Explanation:
The period of a simple pendulum is given by:

where
L is the length of the pendulum
g is the acceleration of gravity
From this equation we can write

Taking the square of this equation, we get:

So we see that
is proportional to L and inversely proportional to g. So, we can write:

So the only correct option is

A heat pump is a device that is capable of transferring heat energy from a source of heat to what is known as the heat sink. It also moves thermal energy in the opposite direction of a spontaneous heat transfer through heat absorption from a cold space and releasing it to a warmer space.
When a heat pump is being utilized for heating, it employs the same principle with that of the refrigeration cycle used by an air conditioner or a refrigerator, but in the opposite direction since it releases heat into a conditioned space rather than the surrounding environment. Moreover, heat pump resembles much as refrigeration since it has the same components with the latter except for the presence of a reverse valve.