Question:
How long does it take Rick to cover the distance D?
Answer:
The time, , Rick takes to cover the distance D is;
Explanation:
Here we have the running speed of Rick = and
The walking speed of Rick =
Therefore, since Rick walks half of the distance and runs the other half, we have
Where
Distance for walking = D/2 and distance for running = D/2
Rick's time in running is
and time in walking is
Total time is given by
Considering the equivalence between mass and energy given by the expression of Einstein's theory of relativity, the correct answer is the last option: the energy equivalent of an object with a mass of 1.05 kg is 9.45×10¹⁶ J.
The equivalence between mass and energy is given by the expression of Einstein's theory of relativity, where the energy of a body at rest (E) is equal to its mass (m) multiplied by the speed of light (c) squared:
E=m×c²
This indicates that an increase or decrease in energy in a system correspondingly increases or decreases its mass, and an increase or decrease in mass corresponds to an increase or decrease in energy.
In other words, a change in the amount of energy E, of an object is directly proportional to a change in its mass m.
In this case, you know:
Replacing:
E= 1.05 kg× (3×10⁸ m/s)²
Solving:
<u><em>E= 9.45×10¹⁶ J</em></u>
Finally, the correct answer is the last option: the energy equivalent of an object with a mass of 1.05 kg is 9.45×10¹⁶ J.
Learn more:
This question is wrong because of not correct values.The Correct question is
A gas in a cylinder is held at a constant pressure of 1.80×10⁵Pa and is cooled and compressed from 1.70m³ to 1.20m³. The internal energy of the gas decreases by 1.40×10⁵J.
(a) Find the work done by the gas.
(b) Find the absolute value of the heat flow, |Q|, into or out of the gas, and state the direction of the heat flow.
(c) Does it matter whether the gas is ideal? Why or why not?
Answer:
(a) W= -9×10⁴J
(b) |Q|=2.3×10⁵
(c) It does not matter whether gas is ideal or non-ideal
Explanation:
Given
V₁=1.70m³
V₂=1.20m³
p=1.8×10⁵ pa
ΔU= -1.40×10⁵J
For (a) work done by gas
For (b) Heat flow |Q|
|Q|=ΔU+W
For (c) part
It does not matter whether the gas is ideal or not because the first law of thermodynamics which applied in our solution could applied to any material ideal or non ideal
according to newton's first law, an object maintains its state of rest or motion unless acted upon by an external force. So a force is required to stop an object at rest and a force is also required to move an object at rest.
when the hockey player send a hockey puck flying across the ice , frictional force from the ice surface acts on the puck in opposite direction of the motion of puck to slow it down and stops it finally.