Answer:
B.) a wheel and axle and a lever
Explanation:
P.S - The exact question is -
Given - A wheelbarrow can be used to help lift a load, such as a pile of dirt, and then push the load across a distance. A man pushes a wheelbarrow.
To find - Which simple machines make up a wheelbarrow?
A.) a pulley and an inclined plane
B.) a wheel and axle and a lever
C.) a pulley and a wheel and axle
D.) a lever and a wedge
Proof -
The correct option is - B.) a wheel and axle and a lever
Wheelbarrows are used to carry more goods from place to place by using minimal force as compared when goods are carried by hand.
With this machine, During hauling people can save time.
Answer: Revolution
Explanation:
The Earth rotates about its axis in 23 hours 56 minutes i.e. in one day. The Earth revolves around the Sun in one year (365 and 6 hours). Axis is an imaginary line passing through the center of any body about which it rotates. Solstice is an event when Sun is passing over Tropic of Capricorn or Tropic of cancer.
Hence, the correct option is The earth completes one <u>Revolution</u> when it travels once around the sun.
To determine the heat released by the process of condensation, we simply multiply the amount of the gas that condensed to the latent heat of vaporization. We do as follows:
Heat released = 21 J/g (12.0 g ) = 252 J of heat released
<h2>
Answer: 26,8 s</h2>
Explanation:
If we are talking about an acceleration at a constant rate , we are dealing with constant acceleration, hence we can use the following equations:
(1)
(2)
Where:
is the final velocity of the plane (the takeoff velocity in this case)
is the initial velocity of the plane (we know it is zero because it starts from rest)
is the constant acceleration of the plane to reach the takeoff velocity
is the distance of the runway
is the time
Knowing this, let's begin with (1):
(3)
(4)
(5)
Substituting (5) in (2):
(6)
Finding :
This is the time needed to take off
