Physics Answers

If the density of water is 1,00 g/cm° and atmospheric pressure is 1,013 x 105 Pa, the depth in water (in m) where the absolute pressure is four times atmospheric

pressure, is equal to:

 ball with a diameter of 20,00 cm is placed in water with 75% of its volume above the surface of the water. The buoyant force of the water on the ball is…?

water is flowing through a pipe with a constriction. The diameter of the narrow section is one-half the diameter of the wide section. If the velocity of the incompressible

fluid is 3,20 m/s in the wide section, then what is the velocity of the fluid in the narrow section?

An object is placed between a converging

lens and a plane mirror. Explain how two real images of the object may be

produced by the system. If the focal length of the lens is 15 cm and the object is 20 cm from both the lens and the mirror. Calculate the distances of the two images from the lens.

The orbital time of Neptune around the Sun is 165 Earth years and its orbital path is 30 times longer than that of the Earth.

a) Calculate the orbital speed of Neptune relative to the Earth. orbital speed

b) State how the speed of travel of Neptune compares with that of the Earth.

Calculate the density of the moon by assuming it to be a sphere of diameter 3475 km and having a mass of 7.35 × 1022 kg. Express your answer in g/cm3

When the driver of a car travelling at 72km/h suddenly sees a pedestrian in front of the car , he applies the brakes. Consider the reaction time of the driver is 0.2s. if the maximum deceleration that the brakes can produce is 20m/s², Find the maximum stopping distance for the car

A stone is thrown vertically upwards from the ground with an initial velocity of 20ms-1.

a)What is the maximum height reached?

b)How long does the ball take to reach this maximum height?

c)How long does it take for the ball to fall to the ground again from the maximum height?

A ball falls 20meters from rest to the ground below

a)What is the velocity as it strikes the ground?

b)How long does it take to fall?

A stone takes 3s to reach the ground. What is the height above the ground ?