Answer:
Distance is 500 m, displacement is 0
Explanation:
Distance and displacement are defined in two different ways:
- Distance is the total length of the path covered by an object in motion - so it depends on the path taken. In this problem, the distance travelled by the car corresponds to the length of one lap, which is the length of the track, so 500 m
- Displacement is the distance in a straight line between the final point and the initial point of the motion. This means that displacement does not depend on the path taken, but only on the starting and ending point of the motion. In this problem, the car completes one lap, so the final position of the car is equal to its starting position - therefore the displacement is zero, since the distance between these two points is zero.
Answer: a meteoroid is debris in space. If part of that debris comes into Earth's atmosphere, it becomes a meteor.
Explanation:
Answer:
N = 648.55[N]
Explanation:
To solve this problem we must use Newton's second law which tells us that the sum of forces on a body is equal to the product of mass by acceleration.
∑F = m*a
where:
∑F = Forces applied [N]
m = mass = 73.2 [kg]
a = acceleration = 0.950 [m/s²]
Let's assume the direction of the upward forces as positive, just as if the movement of the box is upward the acceleration will be positive.
By performing a summation of forces on the vertical axis we obtain all the required forces and other magnitudes to be determined.

where:
g = gravity acceleration = 9.81 [m/s²]
N = normal force (or weight) measured by the scale = 83.4 [N]
Now replacing:
![-(73.2*9.81)+N=-73.2*0.950\\-718.092+N=-69.54\\N = -69.54+718.092\\N = 648.55[N]](https://tex.z-dn.net/?f=-%2873.2%2A9.81%29%2BN%3D-73.2%2A0.950%5C%5C-718.092%2BN%3D-69.54%5C%5CN%20%3D%20-69.54%2B718.092%5C%5CN%20%3D%20648.55%5BN%5D)
The acceleration has a negative sign, this means that the elevator is descending at that very moment.
(b) 71%
The thermal efficiency of a Carnot heat engine is given by:

where
W is the useful work done by the engine
is the heat in input to the machine
In this problem, we have:
is the heat absorbed
is the work done (175 kJ is the heat released to the sink, therefore the work done is equal to the difference between the heat in input and the heat released)
So, the efficiency is

(a) 
The efficiency of an engine can also be rewritten as

where
is the absolute temperature of the cold sink
is the temperature of the source
In this problem, the temperature of the sink is

So we can re-arrange the equation to find the temperature of the source:
