Answer:
Explanation: so how many minutes are in an hour 60 right, and the bus travels 10km in 7 minutes right so use math the bus travels 14km in 10 minutes so the bus travels 98km in an hour
To solve this problem we will apply the concepts related to the thermal efficiency given in an engine of the Carnot cycle. Here we know that efficiency is given under the equation

Where,
Temperature of Cold Body
Temperature of Hot Body
= Efficiency
According to the statement our values are:


Replacing we have that




Therefore the temperature of the heat source is 300K
Answer:
0.074m/s
Explanation:
We need the formula for conservation of momentum in a collision, this equation is given by,

Where,
= mass of ball
= mass of the person
= Velocity of ball before collision
= Velocity of the person before collision
= velocity of ball afer collision
= velocity of the person after collision
We know that after the collision, as the person as the ball have both the same velocity, then,


Re-arrenge to find
,

Our values are,
= 0.425kg
= 12m/s
= 68.5kg
= 0m/s
Substituting,


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<em>The speed of the person would be 0.074m/s after the collision between him/her and the ball</em>