Classical Mechanics Answers

Show complete solution: Use the correct number of significant figures.

1. A soccer ball is kicked from the ground with an initial speed of 19.6 m/s at an upward angle of 46.4˚. A player 50.6 m away in the direction of the kick starts running to meet the ball at that instant. What must be his average speed if he is to meet the ball just before it hits the ground? Neglect air resistance.

Answer: _________
( the tolerance is +/-2%)

2. A batter hits a pitched ball when the center of the ball is 1.27 m above the ground.The ball leaves the bat at an angle of 45° with the ground. With that launch, the ball should have a horizontal range (returning to the launch level) of 100 m.

(a) Does the ball clear a 7.41-m-high fence that is 90.0 m horizontally from the launch point?

(b) At the fence, what is the distance between the fence top and the ball center?

A 750 g block can slide uniformly along the horizontal track when a string attached to it has the other end passed through a pulley with added mass of 180 g. What is the friction force between the block and the track?

A. 1.76 N
B. 7.35 N
C. 0.42 N
D.423.36 N

If you have two high-velocity gyros rotating on the same axis with the same center of mass in opposite directions, what happens to precession when tilted? Will they still have the same stabilizing effects as if they were going in the same direction.

magnitude of work to stop a rolling sphere

You are doing an experiment, trying to determine which has more effect on potential energy, height or mass. You take two cupcakes. One cupcake you add mass to, and drop from 3 meters. The other you don’t add mass to and drop from 1 meter. Which is more important in potential energy, height or mass? Show why in the equation.

Johan climbs a cliff wall. He is attached to an elastic safety rope that is 13.0 m long and has a spring constant of 1.2 kN / m. The safety line is attached to Johan's center of gravity, which is 3.1 m above the safety line's fastening point in the rock wall.
He loses his grip and falls straight down. When the safety line is stretched, the case is braked. During the case, the safety line is extended by 5.5 m.
Johan swings up and down a few times before stopping. He weighs 86 kg.

a) Calculate the oscillation time at the end of the oscillation process.
b) How far below the line's attachment point A does Johan hang when the halt has stopped?
c) Determine Johan's maximum speed during the case.



Data for Experiment 108- Frequency of Vibration

Frequency and Tension

Trial 1 Trial 2

Vibrating Length (L) 50 cm 65 cm
Number of Segments (n) 2 2
Attached Mass (m) 70g 90g
Linear Mass Density 0.0015 g/cm 0.0015 g/cm
Actual Frequency 120 Hz 120 Hz

Find the Following. Use the correct number of Significant Figures.
1. Tension ( T=mg) in Trial 1 and Trial 2
2. Experimental Frequency in both trials.
3. Percentage error in both trials.

Data for experiment 105- Coefficient of Linear Expansion

Aluminum Rod

Initial Length = 70.20 cm
Initial Temperature = 22 degrees Celsius
Final Temperature- = 68 degrees Celsius
Final Length = 70.29 cm
Actual Value of Coefficient of Linear Expansion for Aluminum = 23.80 x10^-6 (degrees Celsius)^-1

Find the Following. Use the correct number of Significant Figures.

1. Experimental Value of Coefficient of Linear Expansion
2. Percentage Error

2 trains trains x &y travel on 2 parallel tracks in same directions with uniform accelerations 15 & 10m/s,pass a railway station at same instance.Speeds of x &y at that moment 72km/h, 108km/h respectively.After some time x passed y at a place.
A)Draw the v-t graph for both x &y in same axis.
B)Determine the time which is taken by x to pass y using that graph

1. Consider the mechanical energy of a body at rest on the ground at the Earth's equator, at
re = 6400 km.

Consider the mechanical energy of the same body at rest on the ground at the South pole, at re = 6400 km. For this problem, we consider the Earth to be spherical.

(Remember, the object at the equator traces a circular path, the object at the Pole does not.)

G = 6.67×10^−11 Nm^2 kg^−2, and the mass of the Earth is M = 5.97×10^24 kg.

a. How much more mechanical energy per kilogram does an object on the ground at the Equator than on the ground at the Pole?

b. E= ___ MJ.kg^−1. (2 sig figs, do not use scientific notation)