Answer:
200 km/hr
Explanation:
Since he goes 80km per hour, multiply this by 2.5 or two and a half hours.
80 x 2.5 = 200 km/hr.
Answer:
The final acceleration of the car, v = 70 m/s
Explanation:
Given,
The initial velocity of the car, u = 20 m/s
The acceleration of the car, a = 10 m/s²
The time period of travel, t = 5 s
Using the I equations of motion
v = u + at
= 20 + 10(5)
= 20 + 50
= 70 m/s
Hence, the final acceleration of the car, v = 70 m/s
1) 29.8 C
At the beginning, the metal is at higher temperature (70.4 C) while the water is at lower temperature (23.6 C). When they are put in contact, the metal transfers heat to the water, until they reach thermal equilibrium: at thermal equilibrium the two objects (the metal and the water have same temperature). Therefore, since the temperature of the water at thermal equilibrium is 29.8 C, the final temperature of the metal must be the same (29.8 C).
2) 6.2 C
The temperature change of the water is given by the difference between its final temperature and its initial temperature:

where

Substituting into the formula,

And the positive sign means that the temperature of the water has increased.
3) -40.6 C
The temperature change of the metal is given by the difference between its final temperature and its initial temperature:

where

Substituting into the formula,

And the negative sign means the temperature of the metal has decreased.
Answer:
even if it all could be used, it wouldn't be enough
Explanation:
The land area of the US is about 5.45% of the world's area, so the amount of released heat over the area of the US is on the order of 2.4 Tw. Current technology for converting geothermal energy to electricity is about 12% efficient, so the available energy might amount to 0.29 Tw if it could all be captured.
Energy consumption in the US in 2019 was on the order of 0.46 Tw. This suggests that even if <em>all</em> of the thermal energy radiated by the Earth from the US could be turned to useful forms of energy, it would meet only about 60% of the US need for energy.