Question

Solve the following questions:

The density (mass per unit volume) of ice is 917kg / m³, and the density of seawater is 1024kg / m³. Only 10.45% of the volume of an iceberg is above the surface of the water. If the volume of a given iceberg is above the water is 4205.3 m³, what is the magnitude of the force that the sea exerts on this iceberg?

A person is standing on the surface of the Earth. The mass of the person is m, and the mass of the Earth is M. The person jumps upwards, reaching a maximum height h above the Earth. When the person is at this height h, the magnitude of the force that the person exerts on the Earth is:

a) mg

b) Mg

c) M²g / m

d) m²g / M

e)zero

Answer 1

1.

Buoyant force, Fb = density of water*4205.3* 9.8= 4.22*10⁷ N

2. A person is standing on the surface of the Earth. The mass of the person is m, and the mass of the Earth is M. The person jumps upwards, reaching a maximum height h above the Earth. When the person is at this height h, the magnitude of the force that the person exerts on the Earth is:

Zero. When the object is in no more contact with the surface of earth its apparent weight is zero.

Option (e) is correct.