Answer: The ice cube would float on top of the water and the rock would sink to the bottom.
Explanation: The ice cube has a smaller density than the rock which allows the ice cube to float but makes the rock sink to the bottom of the glass of water.
Answer: A device records the time it takes sound waves to travel from the surface to the ocean floor and back again. Sound waves travel through water at a known speed. Once scientists know the travel time of the wave, they can calculate the distance to the ocean floor.
Explanation:
Answer:
1.65
Explanation:
The equation of the forces along the horizontal direction is:
(1)
where
F = 65 N is the force applied with the push
is the frictional force
m = 4 kg is the mass
is the acceleration
The force of friction can be written as 
(2), where
is the coefficient of kinetic friction
R is the normal force exerted by the floor
The equation of forces along the vertical direction is
(3)
since the bookcase is in equilibrium. Substituting (2) and (3) into (1), we find
And solving for ,
Answer:
C. 21 Joules
Explanation:
We apply the formula to calculate the potential energy (Ep):
Ep=m*g*h
Where:
Ep : potential energy in Joules (J)
m :mass in kilograms (kg)
g acceleration due to gravity (m/s²)
h: height in meters (m)
Calculation of the height (h)
Ep = m*g*h
7 = (1.5 )*(9.8) *(h
)
7 = (14.7) (h
)
h = 7 / (14.7)
h= 0.476 m
Gravitational potential energy of the second object
Ep = m*g*h
Ep = (4.5 )*(9.8) *(0.476
)
Ep = (4.5 )*(9.8) *(0.476
)
Ep = 21 J
