Answer:
The length of the object would shrink to zero which is not possible.
Explanation:
A rocket or any body cannot reach the speed of light because according to theory of relativity the and the Lorentz factor the length of the object would shrink to zero and the time dilation for that body would be infinite.
The Lorentz factor is given as:
where:
v = speed of the moving object
c = speed of light
Answer:
NO
Explanation:
No, a machine cannot be 100% efficient. This is due to the movement of the moving parts siding against each other and causing friction. This friction is the one that creates heat and causes wear and tear between moving ports f the machine hence making the machine to decrease in efficiency with time
Answer:
Explanation: P = 300 W and t = 2 min = 120 s
Energy Q = Pt = 300 W · 120 s = 36 000 J.
Thus, plate can not produce 45 000 J heat.
Answer:
μ = 0.725
Explanation:
This problem refers to Newton's second law.
F = ma
Let's write the equations on each axis
Y Axis
N-W = 0
N = W
N = mg
X axis
F-fr = ma
With the body not started moving its acceleration is zero
F-fr = 0
F = fr
The friction force equation is
fr = μ N
fr = μ m g
Let's replace and calculate
F = μ m g
μ = F / mg
μ = 321 /45.2 9.8
μ = 0.725