Answer:
F = 47.6 N
Explanation:
- Newton's 2nd law can be expressed as the rate of change of the total momentum, respect of time, as follows:
- So, in order to find the average force exerted by the skater on the wall, we can find the change in momentum due to the force exerted by the wall (which is equal and opposite to the one exerted by the skater), and divide it by the time interval , as follows:
⇒ Fsk = 47.6 N (normal to the wall)
Answer:
100 cc
Explanation:
Heat released in cooling human body by t degree
= mass of the body x specific heat of the body x t
Substituting the data given
Heat released by the body
= 70 x 3480 x 1
= 243600 J
Mass of water to be evaporated
= 243600 / latent heat of vaporization of water
= 243600 / 2420000
= .1 kg
= 100 g
volume of water
= mass / density
= 100 / 1
100 cc
1 / 10 litres.
Answer:
∆PE = 749.7 J
At 0.9 m high, PE = 793.8 J
At 1.75 m high, PE = 1543.5 J
First, we convert kcal to joules:
1 kcal = 4.184 kJ
475 kcal = 1987.4 kJ
Now, calculating the change in internal energy:
ΔU = Q + W; where Q is the heat supplied to the system and W is the work done on the system.
ΔU = -500 + 1987.4
ΔU = 1487.4 kJ
The thermosphere is a layer of Earth's atmosphere. The thermosphere is directly above the mesosphere and below the exosphere. It extends from about 90 km (56 miles) to between 500 and 1,000 km (311 to 621 miles) above our planet.
