RADIATION
There are three types of heat transfer or heat propagation; conduction, convection and radiation. Heat transfer is the process by which heat projects externally however, depending on the temperature and pressure. Also called the movement of heat from a low temperatured state which increases as heat progresses.
Conduction is the heat transfer by contact, immediate contact.
Convection is the transfer of heat through air and water.
<span>Radiation is the transfer of heat regardless of the presence of atoms or particles.<span>
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Well I figured out at his current pace, he would finish the 1100 remaining meters in 200 seconds. However, he needs to complete it in 180 seconds. I'm not sure how to find out how long he has to accelerate at 0.20 m/s/s to complete it in 180 seconds.
Answer:
The change in height of the mercury is approximately 2.981 cm
Explanation:
Recall that the formula for thermal expansion in volume is:

from which we solved for the change in volume
due to a given change in temperature 
We can estimate the initial volume of the mercury in the spherical bulb of diameter 0.24 cm ( radius R = 0.12 cm) using the formula for the volume of a sphere:

Therefore, the change in volume with a change in temperature of 36°C becomes:

Now, we can use this difference in volume, to estimate the height of the cylinder of mercury with diameter 0.0045 cm (radius r= 0.00225 cm):

Answer:
3.36 Joules
Explanation:
Work done= Force × distance
F=4.2 N
distance= 0.8 m
work done= 4.2 × 0.8
work done= 3.36 Joules
letter a because 4N to the left +3N to the right = 4N left minus 3N left as you change the direction of 3N then you also change the plus into minus. the direction will always favour to which of the direction is bigger