Classical Mechanics Answers

An apple is falling down from a height of 20m and hit a person. Assume that the mass of the Apple is 200g. The duration of impact is, 0.001sec, and the area of the bone is 1cm2. Canculate the impulsive force applied to the person

Assume that a 75kg skater on level ice has built up her speed to 3km/hr. Given the respective static and kinetic friction of steel of ice =us=0.02 and uo=0.01. How far will she coast before sliding friction dissipates her energy? Does the distance of the coasting depend on the mass of the skater? Explain why

An object of mass 1kg travels to east with a uniform velocity 2ms-1.A froce of 2N is applied on it along north direction. What's the displacement of object after 2 seconds

Problem 1: determine the tension (T1) in the rope so that the 50 lb block is on the verge of sliding up. The coefficient of static friction between the block and the plane is 0.2, and that between the rope and the drum is 0.3. Will T1 have the same value as tension T2?

An H2 molecule can be formed in a collision that involves three hydrogen atoms. Suppose that before such a collision, each of the three atoms has speed 2000 m/s , and they are approaching at 120 ∘ angles so that at any instant, the atoms lie at the corners of an equilateral triangle. Find the speeds of the H2 molecule and of the single hydrogen atom that remains after the collision. The binding energy of H2 is Δ=7.23×10−19J, and the mass of the hydrogen atom is 1.67×10−27kg.
Enter your answers numerically separated by a comma.

Circular Motion:

1) The radius of the earth at the equator is 6.4 x 10^6 m. Assume that the earth is spherical.
a) determine the instantaneous velocity of a point at the equator
b) determine the centripetal acceleration of a point at the equator

Answers:
a) 465ms-1
b) 3.4 x 10^-2 ms-2

Earth's gravitational field:

1) Describe the gravitational field as it: (include diagram to aid answer)
a) exists within the room within you're sitting
b) as it exists around a planet such as the Earth

2) Outline how the Law of Universal Gravitation can be used to calculate the acceleration due to gravity at the Earth's surface

3) The gravitational field vector g has an average value on the surface of Earth of 9.8Nk-1 or ms-2. Show that the two alternative units quoted are equivalent

A car of mass 1000kg travels around a banked track of radius 200m. The angle of banking is 15 degrees and the speed of the car is such that frictional force is zero. By resolving force components into the vertical and horizontal directions:

a) calculate the value of N, the normal contact force
b) calculate the speed at which the car is travelling

The answers are below but i couldn't figure out to get to them.
a) 9.5x10^3 N
b) 22ms-1

A conical pendulum of mass 3.1kg, string length 3m and at an angle of 20 degrees is set up. Calculate:
a) the radius of the circle traced
b) the tension of the string
c) the period of the motion

The total energy of a particle executing simple harmonic motion of period 2\π s is 0.256J. The displacement of the particle at π/4 is 8\sqrt{2} cm. Calculate the mass of the particle.
a. 20 Kg
b. 50 Kg
c. 15 Kg
d. 30 Kg