Other Physics Answers

Given:

G = 6.67 x 10-11 N m2 kg-2

mass of the Earth = 6.0 x 1024 kg

radius of the Earth = 6.4 x 106 m

gravitational field strength close to the surface of the Earth is 9.8 N

kg-1 15

19. What is the gravitational potential energy of a 60 kg student on

the surface of the Earth? What then, is the minimum energy

that would be required to get this student completely out of the

Earth’s gravitational field?

20. You’re in the design of mission carrying humans to the surface

of the planet Mars, which has a radius of 3.38 x 106 m and a

mass of 6.24 x 1023 kg. The Earth weigh of the Mar’s lander is

39,200 N. Calculate its weight and the acceleration due to Mar’s

gravity at 6.0 x 106 m above the surface of Mars.

1. A flywheel, in the form of uniform disk, is 4.0 m in diameter and

weighs 637 N. What will be its angular acceleration if it is

activated upon by net torque of 225J?

2. When you switch your room fan from medium to high speed, the

blades accelerate at 1.2 radians per second squared for 1.5

seconds. If the initial angular speed of the fan blades is 3.0

radians per second, what is the final angular speed of the fan

blades in radians per second?

A particle of charge 4.25x10-9 C moves at 3.0x10* m/s at 60° up the x-y plane through a uniform magnetic field of 5.0x10-³T directed along the +z-axis. Find the magnetic force on the particle.

1. Every weekend, you and your family always find time to bood with each other. All of your family members are fully vaccinated, and they decided to have a two days vacation in Cebu City. You choose to ride a private helicopter towards your destination. You noticed that the helicopter has two sets of lifting blades, they rotate in opposite directions (and there will be no sail propeller). Explain why it is best to have the blades rotates in opposites directions.

2. When you start the enige of your car with the transmission in restral, you notice that the car rocks in the opposite sense of the engine's rotation. Explain in terms of conservation of angular momentum. Is the angular momentum of the car conserved for long (for more than a few seconds)?

3. In a playground, there is a small merry-go-round. Suppose a child walks from the outer edge of a rotating merry-go-round inside, does the angular velocity of the merry-go-round increase, decrease or remain the same? Explain your answer.

A transverse wave on a taut string is modeled with the wave function

y(x, t) = Asin(kx-wt)

(0.25m) sin(6.48m-'x- 1.47s1 t)

Find the: (a) amplitude, (b) wavelength, (c) period, (d) direction of

: )

propagation and (e) speed of the wave.

Determine the force required to be generated by a flying saucer of mass 1.94 x 10¹⁶ µg to rise from ground level with an acceleration of 5.18 x 10⁸ Km/h upward. (b) Find the work done by this force if the saucer is elevated 196 hm from the ground. 

A sample of an ideal gas is in a vertical cylinder fitted with a piston. As 5.79 kJ of energy is transferred to the gas by heat to raise its temperature, the weight on the piston is adjusted so

that the state of the gas changes from point A to point 8 along the semicircle shown below. Find

the change in internal energy of the gas.

P(kPa)

One mole of an ideal gas is heated slowly so that it goes from the PV state (Pi, Vi) to (3Pi, 3Vi) in such a way that the pressure is directly proportional to the volume. (a) How much work is done on the gas in the process? (b) How is the temperature of the gas related to its volume during

this process?

The average coefficient of volume expansion for carbon tetrachloride is 3.9 x 10-* ("C)-¹, if a 20.0-gal steel container is filled completely with carbon tetrachloride when the temperature is 30.0°C, how much will spill over when the temperature rises to 41.0°C?

Steel train rails on LRT2 are laid in 10.0-m-long segments placed end to end. The rails are laid on a day when their temperature is 28.0°C. (a) How much space must be left between adjacent rails if they are just to touch on a summer day when their temperature is 39.0°C? (b) If the rails are

originally laid in contact, what is the stress in them on a summer day when their temperature is

39.0°C?