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Answer: The velocity of the ball is 30.0 m/s
This can be calculated by using the value of acceleration as 10.0 m/s2 in free fall and the given time of 3.0 seconds. To get the
velocity, one will have to multiply the acceleration with the given time and the
quotient would result to 30.0 m/s. Mostly all object regardless of their mass,
fall to earth with the same acceleration in the absence of air resistance and as
the child drops the ball from a window, it gains speed as it falls.
Answer:
70 cm
Explanation:
0.5 kg at 20 cm
0.3 kg at 60 cm
x = Distance of the third 0.6 kg mass
Meter stick hanging at 50 cm
Torque about the support point is given by (torque is conserved)

The position of the third mass of 0.6 kg is at 20+50 = 70 cm
Answer:
B. 17,705.1 J
Explanation:
The hear released when the mercury condenses into a liquid is given by:

where
m = 0.06 kg is the mass of the mercury
is the latent heat of vaporization
For mercury, the latent heat of vaporization is
, so the heat released during the process is:

So, the closest option is
B. 17,705.1 J