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Projectile velocity: Boy throws a stone from the edge of a cliff

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.

Rotational Kinematics

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

Force, speed

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!

7 Physics problems: Kinetic Energy, work, force, magnitude, speed

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

Vectors and velocity: Speed of Romeo's pebbles when they hit Juliet's window

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

Vectors and velocity of cannonballs projected upward and forward

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

Acceleration, distance, and velocity of Car A and Car B

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

Rod and mass system: Find velocity and tensions in the rod.

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

Projectile motion

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?

Car moves over the arc of a bridge. Find the maximum speed; force bridge exerts.

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

Boat leaves one bank of a river so as to arrive downstream across river.

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

Physics: 8 word problems about velocity, distance, rotation, volume, time, speed

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

Whirling stone: Maximum velocity

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

Momentum and magnitude of mass; impulse; force

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.

Submarine A detects sound from sub B. Find the velocity of sub B.

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

Object of mass 2M moving with SHM: Find period, velocity, amplitude

SEE ATTACHMENT #1 for diagram showing parameters, and general equations of SHM. Driven by a spring with force constant k, on a horizontal frictionless table, two joined masses, each mass M, is executing SHM between xm and -xm. Known parameter values are: M= 2 kg, k= 64 nt/m, xm= .25 m, PART a. Find the period, and max