<span>The heat energy is being transferred between the two substances by thermal conduction. Because the hot coffee is at a different temperature to the mug, heat energy flows between them so that they reach thermal equilibrium, or the same temperature. This kind of heat transfer always happens from hotter temperatures to cooler temperatures.</span>
(C)
Explanation:
Doubling the distance will make the force only 1/4 of the original value.
The acceleration due to gravity is 3 m/s^2 and the work done is -4.3 J.
<h3>What is the acceleration due to gravity?</h3>
Now we must use the formula;
h = ut + 1/2gt^2
Since it was dropped from a height u = 0 m/s
h = height
u = initial velocity
g = acceleration due to gravity
t = time
h = 1/2gt^2
g = 2h/t^2
g = 2 * 2.85 /(1.38)^2
g = 5.7/1.9
g = 3 m/s^2
The work that must be done is against gravity hence;
W = -(mgh)
W = - (0.5 kg * 3 m/s^2 * 2.85 m)
W = - 4.3 J
Learn more about acceleration due to gravity:brainly.com/question/13860566
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The angular speed is equal to 40rotations per min
Answer:
Acceleration(a)=3m/s^2
Time(t)=1min[1min=60s]
=1×60
=60s
Initial velocity(u)=0m/s
Velocity(v)=?
We know that,
Acceleration=v-u/t
Or,3m/s^2=v-0/60
Or,3×60=v-0
Or,v=180m/s
So,the velocity is 180m/s.
Hope,it will helpyouu!