Answer:
The coefficient of friction causes the force on the object to be less than its initial reading on the spring scale.
Explanation:
Since the block reads 24.5 N before the block starts to move, this is its weight. Now, when the block starts to move at a constant velocity, it experiences a frictional force which is equal to the force with which the student pulls.
Now, since the velocity is constant so, there is no acceleration and thus, the net force is zero.
Let F = force applied and f = frictional force = μN = μW where μ = coefficient of friction and N = normal force. The normal force also equals the weight of the object W.
Now, since F - f = ma and a = 0 where a = acceleration and m = mass of block,
F - f = m(0) = 0
F - f = 0
F = f
Since the force applied equals the frictional force, we have that
F = μW and F = 23.7 N and W = 24.5 N
So, 23.7 N = μ(24.5 N)
μ = 23.7 N/24.5 N
μ = 0.97
Since μ = 0.97 < 1, the coefficient of friction causes the force on the object to be less than its initial reading on the spring scale.
<h2>Astronaut travels to different planets - Option 4 </h2>
If an astronaut travels to different planets, none of the planets will the astronaut’s weight be the same as on Earth. On jupiter, weight will be more than the weight on earth. For instance if an astronaut has 100kg on earth then he will have 252 kg on jupiter.
On Mars, weight will be less than the weight on the earth. For instance, if an astronaut has 68 kg on earth then he will has 26 kg on mars. On Mercury, weight of an astronaut will be less than the weight on earth. Example if he has 68 kg on earth then he will have 25.7kg on mercury.
Hence, none of these planets the weight of astronaut will be same as on earth.
Answer:
C ) 1.53
Explanation:
The critical angle of a material is given by the formula

where
c is the critical angle
n is the refractive index
This formula is valid if the second medium is air (which is the case of the problem).
In this problem, we know the critical angle:

Therefore we can rearrange the equation to find the refractive index:

The compressor constricts the refrigerant vapor, raising its pressure, and pushes it into the coils on the outside of the refrigerator. 2. When the hot gas in the coils meets the cooler air temperature of the kitchen, it becomes a liquid. ... The refrigerant absorbs the heat inside the fridge, cooling down the air.