1. heat engine ~~ •a machine that converts the internal energy of a fuel into mechanical energy.
2. heat pump ~~ •an appliance that extracts heat energy from one source and deposits it
3. Boiler ~~ •a heating appliance that uses heat energy released from fossil fuels to warm water for use in radiant or
convection heating systems.
4. Thermostat ~~ •an appliance that controls the maintenance temperature of a heating
1) Yes, it is a conservative force
2) The potential energy at (5m, 5m) is 20 J
A force is defined to be conservative if the work done by the force when moving an object does not depend on the path taken, but only on the initial and final position of the object.
Let's verify if this condition is met for the force in this problem:
- For going from (0 m, 0 m) to (5 m, 5 m), the work done is 20 J (A)
Then we can go from (0 m, 0 m) to (5 m, 5 m) through a different path:
- from (0 m, 0 m) to (5 m, 0 m) (work done: 25 J)
- from (5 m, 0 m) to (5 m, 5 m) (work done: -5 J)
Total work done in the second path: 25 J + (-5 J) = 20 J --> same as (A)
We can also go from (0 m, 0 m) to (5 m, 5 m) through a different path:
- from (0 m, 0 m) to (0 m, 5 m) (work done: 35 J)
- from (0 m, 5 m) to (5 m, 5 m) (work done: -15 J)
Total work done in the third path: 35 J + (-15 J) = 20 J --> same as (A)
So, the force is conservative, since the work done does not depend on the path taken.
For a conservative force, the change in potential energy of the object moved by the force is equal to the work done by the force in moving the object from A to B.
Point A: (0m, 0m)
Point B: (5m, 5m)
So, the change in potential energy is equal to the work done from A to B:
is the potential energy in point B
is the potential energy in point A
In this problem, the potential energy at the origin (point A) is zero, so
Also we know that the work done is
W = 20 J
So, we find
Learn more about potential energy:
The acceleration is
We can answer this question by using Newton's second law, which states that the net force acting on an object is equal to the product between the mass of the object and its acceleration:
F is the force
m is the mass
a is the acceleration
In this problem, we have
m = 25 kg is the mass of the rider+bicycle
F = 400 N is the force
Solving for a, we find the acceleration:
Learn more about Newton's second law:
Power consumed = 2250 watt
When resistive loads are connected in parallel to a voltage source, the powers are additive.
Power consumed = Number of lamps * Power consumed by each lamp
Power consumed = 9 * 250