The force on the box is:
F = mgsin∅
If we multiply by this with the distance it traveled, we will know the work done by the box.
W = dmgsin∅
This work will be converted to elastic potential energy in the spring which is:
1/2 kx². Equating these and substituting values:
1/2 * 170 * x² = 4 * 13 * 9.81 * sin(30)
x = 1.73 m
The box's maximum speed will at the point right before contact with the spring, when the compression is 0.
Answer:
Both of them reach the lake at the same time.
Explanation:
We have equation of motion s = ut + 0.5at²
Vertical motion of James : -
Initial velocity, u = 0 m/s
Acceleration, a = g
Displacement, s = h
Substituting,
s = ut + 0.5 at²
h = 0 x t + 0.5 x g x t²
Vertical motion of John : -
Initial velocity, u = 0 m/s
Acceleration, a = g
Displacement, s = h
Substituting,
s = ut + 0.5 at²
h = 0 x t + 0.5 x g x t²
So both times are same.
Both of them reach the lake at the same time.
Answer:
The boat
Explanation:
Momentum is mass times speed.
p = mv
For the car:
p = (5000 kg) (10 m/s)
p = 50,000 kg m/s
For the boat:
p = (2000 kg) (40 m/s)
p = 80,000 kg m/s
Answer:
D
Explanation:
Copper wire at higher temperature
The operating coefficient or performance coefficient of a heat pump is the ratio between the heating or cooling provided and the electricity consumed. The higher coefficients are equivalent to lower operating costs. The coefficient can be greater than 1, because it is a percentage of the output: losses, other than the thermal efficiency ratio: input energy. Mathematically can be written as,
Replacing,
Therefore the heat is 3.822kJ