Q. A boy throws a stone from the edge of a cliff with an initial speed (Vo) at an angle of 30 degrees above the horizontal. when it hits the surface of a lake 22m below the top of the cliff, the stone is moving at a speed of 25 meters per second. what was its initial velocity.
A solid sphere of uniform density starts from rest and rolls without slipping a distance of d = 4.2 m down a q = 23° incline. The sphere has a mass M = 4.1 kg and a radius R = 0.28 m. a) Of the total kinetic energy of the sphere, what fraction is translational? b) What is the translational kinetic energy of the sphere when i
Hi. Here's a tricky one (for me, anyway): "A train has a mass of 5.07 x 10^6 kg and is moving at 75.5 km/hr. The engineer applies the brakes, which results in a net backward force of 1.71 x 10^6 N on the train. The brakes are held on for 26.0 s. What is the new speed of the train?" Thank you!
1. A luge and its rider, with a total mass of 85 kg emerges from a downhill track onto a horizontal straight track with an initial speed of 37 m/s. If they stop at a constant deceleration of 2.0 m/s^2, (a) What magnitude F is required for the deceleration force, (b) what distance "d" do they travel while decelerating (c) what wo
A catapult on a cliff launches a large round rock towards a ship from a H of 33.0 m above sea level, directed at an angle above the horizontal with an unknown speed v(0). The projectile remains in flight for 6.00 seconds and travels a horizontal distance D of 169 m. Assuming that air friction can be neglected, calculate the valu
A vertical spring (ignore its mass), whose spring constant is 900 N/m, is attached to a table and is compressed 0.150m. What speed can it give to a .300-kg ball when released? How high above its original position (spring compression) will the ball fly?
See attached Word file. Romeo is chucking pebbles as gently as he can up to Juliet's window. That is, he wants the pebbles to hit the window with the least possible speed, as shown in the figure below. He is standing at the edge of a rose garden at H = 7.40 m below her window and at D = 8.60 m from the base of the wall. How f
See attached Word file. The pictures show cannonballs of two different masses projected upward and forward. The cannonballs are projected at various angles above the horizontal, but all are projected with the same vertical component of velocity. Which of the following statements are true about the situations depicted in t
Car A accelerates from rest with 2m/sec^2 and Car B is moving with a constant velocity of 25 m/s. at the instant t=0. Determine (a) distance between the two cars at t=5 sec. (b) time for the cars to arrive at the same location. (c) distance of car A from the origin when they arrive at the same location. (d) speed
A bullet whose mass M1= .04 kg traveling horizontallyhits a stationary block of mass M2= 2.4 kg on a horizontal surface. After the impact, the block, with embedded bullet, slides distance x= 5 meters to a stop. The coefficient of friction is f= .50 between block and surface. Find the velocity V1 of the bullet before impact.
A rigid rod with negligible mass has a length L= 2.6 m. The rod can rotate freely about a fixed pivot at one end. Attached at the other end of the rod is mass M1 = 8.4 kg, and at its center is mass M2 = 3.6 kg. The system is released from vertical at rest to rotate about the pivot. SEE ATTACHMENT #1 for a diagram showing parame
A projectile is fired in such a way that its horizontal range is equal to three times its maximum height. What is the angle of projection?
A soccer player kicks a rock horizontally off a 40.0m high cliff into a pool of water. If the player hears the sound of the splash 3.00s later, what was the initial speed given to the rock? Assume the speed of sound in air to be 343m/s
On a country road, a car whose mass is 1800 kg drives over a bridge which forms a circular arc whose radius is 80 meters. PART a. Find the maximum speed of the car at the highest point of the bridge, in order that the car barely remains in contact. PART b. If the speed of the car at the highest point is 21 m/sec, find t
SEE ATTACHMENT #1 for a diagram showing known parameters. A crate whose mass is 1600 kg, suspended from a cable, is initially moving downward at 12 m/sec. It is brought to a stop in 42 m distance. Find the force in the cable.
ATTACHMENT #1 shows known parameters and vector polygon required. A light plane flies with airspeed (relative to the air) of 500 km/hr. The pilot sets out to fly to a city 800 km due north and finds that the plane must be headed 10 degrees east of north to fly in a straight line to the city. She arrives in 2.0 hours. Find
A marble is fired from ground level. At a height of 9.1 m, its velocity is v=7.6 i + 6.1 j in which (i and j are unit vectors). Find the maximum height attained and the total flight time from release to impact.
A rock is dropped off the side of a bridge and hits the water below 2 seconds later. What was the rock's velocity when it hit the water? What was the rock's average velocity as it fell?
SEE ATTACHMENT #1 for a diagram showing known parameters. A boat leaves one bank of a river and heads in such a direction as to arrive at a point downstream and across the river. A certain river is 2000 meters wide and flows Southward at 6.2 m/sec. The boat's speed relative to the water is 15 m/sec. From a point on the Wes
A rock is given initial upward velocity of 49 m/sec at ground level. Find the change in height in the last 1.5 seconds of its upward motion.
Until 1883, every city and town in the US kept its own local time. Today, travelers reset their watches only when the time change equals 1.0h. How far, on the average must you travel in degrees of longitude until your watch must be reset by 1.0h? (hint: Earth rotates 360 degrees in about 24 hours ) Gold, which has a mass of
A 1000-kg Volkswagen with speed 30m/sec collides head-on with a large truck of mass 10,000kg and speed 25m/sec. As a result of the collision, the two vehicles lock together. a. Find the magnitude and the direction of the velocity of the vehicles right after the collision. b. Compute the total Kinetic energies before
A wave having frequency 20Hz and wavelength 5m is traveling away from its source. What is the distance traveled by this wave in 15 sec?
A man whirls a stone round his head on the end of a string 2 m long. Can the string be in a horizontal plane ? If the stone has a mass of 200g and the string will break if the tension exceeds 4 Newton, what is the smallest angle the string can make with the horizontal ? What is then the speed of the stone ? Take g = 10m/s^2
A constant force acts on a 2kg mass for 3sec while the velocity changes from 4m/sec to 10m/sec. a. Find the initial and final momentum of the mass. b. Find the change in momentum and the impulse given to the mass. c. Find the magnitude of the force.
A 30kg girl moving with speed 2m/sec and a 50kg boy moving with speed 1m/sec collide head-on on an ice-skating rink. As a result of the collision, the girl moves at 1m/sec opposite to her initial direction. Find the magnitude and direction of the boy's velocity after the collision.
A 3000kg truck crashes into a wall at 40km/hr and comes to a stop in 0.5 sec. What is the average force on the truck while it comes to a stop?
How long does it take to stop a 3X10-5kg mass moving at 2X104m/sec by applying a stopping force of 12N on this mass?
Submarine A detects sound from sub B. Given the frequency received and knowing that emitted, find the velocity of sub B. Submarine A, with velocity 21 m/sec, receives from directly behind it, the sound with frequency 266 cy/sec, from submarine B which is known to emit sound at 265 cy/sec. The two submarines are 1800 meters
SEE ATTACHMENT #1 for the general form of the equation of standing waves. A standing wave is set up in a guitar string. Find the first harmonic frequency. Then for a new frequency find new string tension and length. A guitar string is .64 m long and has a linear density of .0004 kg/m. The tension is set at 55 newtons.