Answer:
DU = 21 KJ
Explanation:
Given the following data;
Quantity of heat = 125 KJ
Work = 104 KJ
To find the change in internal energy;
Mathematically, the change in internal energy of a system is given by the formula;
DU = Q - W
Where;
DU is the change in internal energy.
Q is the quantity of energy.
W is the work done.
Substituting into the formula, we have;
DU = 125 - 104
DU = 21 KJ
No. Terrance cannot move the sled. This is because, the force that he produces is 80*3 Newton’s, which is only 240 Newton’s, but since the sled needs a force of 250 Newton’s, he cannot move the sled (even though the difference is only by 10 Newton’s).
Answer:
Time take to fill the standing wave to the entire length of the string is 1.3 sec.
Explanation:
Given :
The length of the one end 
, frequency of the wave 
= 2.3 Hz, wavelength of the wave λ = 1 m.
Standing wave is the example of the transverse wave, standing wave doesn't transfer energy in a medium.
We know,
∴ 
λ
Where 
speed of the standing wave.
also, ∴ 
where 
time take to fill entire length of the string.
Compare above both equation,
⇒ 
sec
Therefore, the time taken to fill entire length 0f the string is 1.3 sec.
Electro waves in a vacuum air is deals with this and electricity when the air and the electricity it makes electro magnets.
