Quantum Mechanics Answers

2. Using arc method calculate the elasticity of demand for oranges when the price

rises from $2 to $3 Price per orange, its demand reduces from 80 thousands oranges

to 70 thousands oranges. Interpret your answer in term of the farmer’s revenue.

(10) A 65 kg hiker climbs to the top of a 3700m high mountain. The climb is made in 5.0 h

starting at an elevation of 2300m. Calculate the following:

a) The work done by the hiker against gravity

b) The average power output in watt and in horsepower

c) Assuming the body is 15% efficient, what rate of energy input was required?

9. A driver notices that her 1150 kg car slows down from 85 km/h to 65 km/h in about 6.0 s

on the level when it is in neutral. Approximately what power (Watts and hp) is needed to

keep the car travelling at constant speed of 75 km/h?

8. You drop a ball from a height of 2.0 m and it bounce back to a height of 1.5 m

a) What fraction of its initial energy is lost during the bounce?

b) What is the ball’s speed just as it leaves the ground after the bounce?

c) Where did the energy go?

6. What is the minimum work needed to push a 950 kg car 810 m up along a 9.0° incline?

a) Ignore friction

b) Assume the effective coefficient of friction retarding the car is 0.25

5. What is the apparent weight of a 75 kg astronaut 4200 km from the centre of Earth’s

moon in a space vehicle?

a) Moving at constant velocity

b) Accelerating toward the moon at 2.9 m/s2

2. A ball on the end of a string is revolved at uniform rate in vertical circle of radius 72.0

cm. If its speed is 4.00 m/s and mass of 0.3 kg. Calculate the tension

in the string when ball is:

a) At top of its path

b) At bottom of its path

1. For a car travelling with speed v around a curve of radius r.

a) Determine a formula for the angle at which a road should be banked so that no

friction is required.

b) What is this angle for an expressway off-ramp curve of radius 50 m at a design

speed of 50 km/h?

An 18.0 Kg is released on a 37° incline and accelerates down the incline at 0.270

m/s2. Find the friction force impeding its motion. How large is the coefficient of

kinetic friction?

If an electron of angular L and spin S Quantum numbers placed in external magnetic field B. If electron is in initial condition n2 write its hamiltonian and analyze its zeeman spectrum?