Well if its a solid that your heating up then it would closely resemble a liquid and a gas. would be able to give a better answer if you provided more information
Answer:
B. 81
Explanation:
When you multiply two numbers, round the answer to the least number of significant figures available. 67.6 has three significant figures, and 1.2 has two significant figures. So we round to two significant figures.
Answer:
Velocity of electron will be 
Explanation:
We have given distance across the plate d = 2 mm 
Potential difference V = 6 volt
We know that potential difference at any distance is given by
V = Ed , here V is potential difference, E is electric field and d is distance
So 
Charge on electron 
We know that expression of velocity is given by
, here q is charge on electron, E is electric field and d is distance
So 
Answer:
8) 709.8875 J
9) The object is at 7.24375 m from the ground
10) Kinetic energy increases as the object falls.
Explanation:
We use the expression for the displacement h(t) as a function of time of an object experiencing free fall:
h(t) = hi - (g/2) t^2
hi being the initial position of the object (10m) above ground, g the acceleration of gravity (9.8 m/s^2), and t the time (in our case 0.75 seconds):
h(0.75) = 10 - 4/9 (0.75)^2 = 7.24375 m
This is the position of the 10 kg object after 0.75 seconds (answer for part 9)
Knowing this position we can calculate the potential energy of the object when it is at this height, using the formula:
U = m g h = 10kg * 9.8 (m/s^2) * 7.24375 m = 709.8875 J (answer for part 8)
Part 10)
the kinetic energy of the object increases as it gets closer to ground, since its velocity is increasing in magnitude because is being accelerated in its motion downwards.