Answer:
53
Explanation:
Because there are 1609.34 meters in a mile. 1609.34÷30=53.64 but because you put one at the beginning of the mile it will stay 53 and not round up to 54
Answer: Around 364 to 480
Answer:
false statement : b ) For the motion of a cart on an incline plane having a coefficient of kinetic friction of 0.5, the magnitude of the change in kinetic energy equals the magnitude of the change in gravitational potential energy
Explanation:
mechanical energy = potential energy + kinetic energy = constant
differentiating both side
Δ potential energy + Δ kinetic energy = 0
Δ potential energy = - Δ kinetic energy
first statement is true.
Friction is a non conservative force so inter-conversion of potential and kinetic energy is not possible in that case. In case of second option, the correct relation is as follows
change in gravitational potential energy = change in kinetic energy + work done against friction .
So given 2 nd option is incorrect.
In case of no change in gravitational energy , work done is equal to
change in kinetic energy.
Answer:
Explanation:
There will be loss of potential energy due to loss of height and gain of kinetic energy .
loss of height = R - R cos 14 , R is radius of hemisphere .
R ( 1 - cos 12 )
= 13 ( 1 - .978 )
h = .286 m
loss of potential energy
= mgh
= m x 9.8 x .286
= 2.8 m
gain of kinetic energy
1/2 m v ² = mgh
v² = 2 g h
v² = 2 x 9.8 x 2.8
v = 7.40 m /s
