Answer:
Zero
Explanation:
It is given that,
A person swims to the other end of a 20m long pool and back.
We need to find his displacement.
Displacement = shortest path covered
He reaches at the same position as from where he has started. It means the shortest path covered is equal to 0 i.e. his displacement is zero.
Answer:
The approximate change in entropy is -14.72 J/K.
Explanation:
Given that,
Temperature = 22°C
Internal energy 
Final temperature = 16°C
We need to calculate the approximate change in entropy
Using formula of the entropy
Where, 
= internal energy
T = average temperature
Put the value in to the formula
Hence, The approximate change in entropy is -14.72 J/K.
The correct answer is letter C. Volume is decreasing. For a fixed amount of an ideal gas kept at a fixed temperature, pressure and volume<span> are </span>inversely proportional<span>. </span>
<h3>
Answer:</h3>
49 N
<h3>
Explanation:</h3>
<u>We are given;</u>
- Mass of the brick as 3 kg
- The coefficient of friction as 0.6
We are required to determine the force that must be applied by the woman so the brick does not fall.
- We need to importantly note that;
- For the brick not to fall the, the force due to gravity is equal to the friction force acting on the brick.
- That is; Friction force = Mg
But; Friction force = μ F
Therefore;
μ F = mg
0.6 F = 3 × 9.8
0.6 F = 29.4
F = 49 N
Therefore, she must use a force of 49 N
