Classical Mechanics Answers

A battle aircraft flying at a velocity of 72ms-1 at an elevation of h=128m to attack an array of identical trucks moving along a straight with different velocities .the dimension of a truck is 10m in length and 3m in height. at the instant the bomb is released freely from the battle aircraft as make 125m displacement with the rear edge of the truck, find the velocity of the truck

I am stationary and throw a ball upward at an angle A with a speed V. Immediately after throwing I start running with a constant acceleration for a period T1 after which I run at constant speed for a period T2. I catch the ball at the same height I threw it from. What is my acceleration ?

Prove the postion of centre of mass or formula?

Consider a spring with a spring constant of 459.8 N /m. How much work in J must be done to compress this spring a distance of 26.7 cm?

If you apply a force F with the x component =-7.24 N and the y component = 8.86 N on a car which moves along the x axis by a displacement of 1.98m. What is the work done on the car by your force in J?

A 54.5 kg skier is moving at 11.4 m/s on a frictionless horizontal, snow covered plateau when she encounters a rough patch 1.1 m long. The coefficient of kinetic friction between this patch and her skis is 0.24. After crossing the rough patch, what is the speed of the skier in ms-1 ? g=9.8ms-2

1. You push your physics book 0.8 m along a horizontal table top with a horizontal push of 4.1 N while the opposing force of friction is 1.9N . How much is the net work done on the book? the answer has the unit of J.

2. A 4 kg watermelon is dropped from rest from the roof of a 6.89 m tall building and feels no appreciable air resistance. Just before it hits the ground, what is the speed of the watermelon (unit is m/s)? g=9.8ms-2

3. Two blocks with different masses m1 and m2 and m1 is larger than m2. They are attached to either end of a light rope that passes over a light, frictionless pulley suspended from the ceiling. The mass are released from rest, and the more massive one starts to descend. After this block has descended 2.6 m, its speed is 2.4 ms-1. If the total mass is 1.4kg, what is the mass of the heavier block m1 (unit is kg)? g=9.8ms-2

If the earth suddenly shrinks to (1/27)th of its original volume with no change in mass, what is the new duration of a day ?

9/10 volume of an ice cube is floating down the surface of sea water.find the density of the ice cube

A speaker, playing a sound at some unknown frequency, is placed near the opening of a tube partially filled with water (the water acts as a fixed boundary). You come into the room and notice that water level in the tube is already dropping. You hear a loud sound (harmonic frequency) and you note the water level is L_A = 1.10 m. You keep listening as the water level falls until you here the next loud sound but you miss the water level. You continue to listen until you hear the next loud sound at L_C = 1.980 m. (If you require the speed of the sound in air, you can take it to be 343 m/s).

A) Sketch any three consecutive harmonics associated with a tube as described above. Label both ends as either fixed or free and label all Nodes and Antinodes.
B) Derive the formula for the harmonic frequencies of this type of tube. State what the allowed values for n are.
C) Find the frequency the speaker is emitting?