The work done on the car is -20 J.
Work done on the car is negative, meaning that the car actually does work on the external system.
<h3>Energy and law of conservation of energy</h3>
- Energy is the ability to do work
- the law of conservation of energy states that the total energy in a system is conserved
From the law of conservation of energy, the initial energy of the car before it moves down the road remains constant or unchanged.
- Initial energy = 100 J
- Initial energy = Final energy - work done on car
- Final Energy = Work done on car + initial energy
80J = Work done on car + 100 J
Work done on car = 80 - 100J
Work done on car = -20 J
Hence, the work done on the car is -20 J
Work done on car is negative.
Since work done on the car is negative, it means that the car actually does work on the external system. Hence, the decrease in the energy of the car.
Learn more about energy and work at: brainly.com/question/13387946
Answer:
Explanation:
Given:
- temperature of skin,
- initial temperature of steam vapour,
- latent heat of steam,
- mass of steam,
- specific heat of water,
- final temperature,
<em>Assuming that no heat is lost in the surrounding.</em>
<u>We know:</u>
<u>Now the total heat given by the steam to form water at the given conditions:</u>
..............................(1)
where:
latent heat given out by vapour to form water of 100°C
heat given by water of 100°C to come at 34°C.
putting respective values in eq. (1)
is the heat transferred to the skin.
Answer:
speed cannot be used to calculate the temperature
Answer:
Wind the long piece of thin wire around the uniform glass rod multiple times, find the length of the total diameters using the metre ruler, and divide by the number of times you wound it around the rod.
Explanation:
Since the diameter of one long piece of thin wire is too thin to be measured by a metre ruler, you can wind it multiple times and push it side by side to get a length you can measure.
For example, if you wound it around 20 times and the total length of 20 diameters of the wire side-by-side is 2.0 cm, one winding, which is the diameter would be 2.0cm ÷ 20 = 0.10cm or 1mm.
The things that a scientist should consider while observing
the force is the environmental conditions,the force that is expected to act on
the dam, the means to contain that force,
and compare different types of designs in accordance with the location
of the dam
