An ideally efficient heat pump delivers 1000 J of heat to room air at 300 K. If it extracted heat from 260 K outdoor air, how mu
1 answer:
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Answer:
v=8m/s
Explanation:
To solve this problem we have to take into account, that the work done by the friction force, after the collision must equal the kinetic energy of both two cars just after the collision. Hence we have
where
mu: coefficient of kinetic friction
g: gravitational acceleration
We can calculate the speed of the cars after the collision by using
Now , we can compute the speed of the second car by taking into account the conservation of the momentum
the car did not exceed the speed limit
Hope this helps!!
ANSWER
EXPLANATION
Since the body is in equilibrium, total upward forces must equal total downward force.
Also the net horizontal forces acting on the body must be zero.
We need to resolve into vertical and horizontal components.
The horizontal component is
.
The vertical component is
.
Equating the up force to the downward forces gives,
.
This implies that,
.
Also the horizontal forces must be equal.
.
Dividing equation (1) by equation (2) gives,
.
.
Therefore the given angle that must make with the horizontal is approximately 35° to the nearest degree.