Answer:
Its mechanical energy is the same.
Explanation:
If forces are only conservative, the mechanical energy will be the same.
It can be different if energy get transformed in another kind of energy like elastic energy for example, although the amount of energy is always the same.
If we just have mechanical energy not geting transformed we have:
Em=K+U
Em: Mechanical energy
K: Kinetic energý
U: Potential energy
Then if Kinetic energy decreases 10J, Potential energy will grow up 10J to keep the same amount of mechanical energy.
The average velocity of Sandy is given by the total distance covered S divided by the total time taken t:

The total distance covered is

while the total time taken is 2 hours + half an hour (for the rest) + 1 hour and half, so

Therefore, the average velocity is
Answer:
Explanation:
Ignoring friction, the acceleration will double
F = ma
2F = m(2a)
Answer:
a)
, b) 
Explanation:
a) The absolute pressure at a depth of 27.5 meters is:



b) The force exerted by the water is:



Answer:
C. less dense than the coffee but more dense than the air above thecoffee.
Explanation: