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Velocity

Velocity of a falling rain drop and air resistance

Please see the attached file for full problem description. Provide solution for Q7 only. Q7. A raindrop is observed at time t=0 when it has mass m and downward velocity u. As it falls under gravity its mass increases by condensation at a constant rate and a resisting force acts on it, proportional to is speed and equal

A rocket is fired vertically upwards with initial speed V and is propelled by ejecting material downwards at a constant rate. To derive the expression for maximum height reached.

(Please refer attachment for detailed problem description) A rocket is fired vertically upwards with initial speed V and is propelled by ejecting material downwards at a constant rate and with a constant speed u relative to the rocket. After a time T the propellant material is exhausted and the rocket still rising. Neglecting

Equations of motion of a rocket

At time t, the mass of a rocket is M(1-kt), where M and k are constants. At time t, the rocket is moving with speed v vertically upwards near the Earth's surface against constant gravity. Burnt fuel is expelled vertically downwards at speed u relative to the rocket. a) Show that (1-kt)dv/dt = ku-g(1-kt) b) Given that v=0 when

Equal masses of inflammable and non-inflammable material.

A body consists of equal masses M of inflammable and non-inflammable material. The body descends freely under gravity from rest. The combustible part burns at a constant rate of kM per second where k is a constant. The burning material is ejected vertically upwards with constant speed u relative to the body, and air resistance m

A woman is standing in the ocean, and she notices that after a wave crest passes, five more crests pass in a time of 50.0s. The distance between two successive crests is 32 m. Determine, if possible, the wave's (a) period, (b) frequency, (c) wavelength, (d) speed, and (e) amplitude. If it is not possible to determine any of these quantities, then so state.

A woman is standing in the ocean, and she notices that after a wave crest passes, five more crests pass in a time of 50.0s. The distance between two successive crests is 32 m. Determine, if possible, the wave's (a) period, (b) frequency, (c) wavelength, (d) speed, and (e) amplitude. If it is not possible to determine any of t

A Juggler is Juggling a Rod One End of Which is Burning

A juggler is juggling a uniform rod one end of which is coated in tar and burning. He is holding the rod by the opposite end and throws it up so that, at the moment of release, it is horizontal, its Center of Mass is traveling vertically up at speed vo and it is rotating with angular velocity wo. To catch it, he wants to arrange

Resultant velocity of a rower crossing a river's current

See attached file for full problem description. a. Rower A wishes to cross a river directly to the opposite bank (east) a distance of 30m. (i.e. at 90 to the shore). The current is flowing NS at 2.6 m/s and he can sustain a rowing speed of 3 m/s.

Velocity of a laser pulse with respect to earth.

A spaceship travels with a speed 0f .6c as it passes Earth. Sometime after passing earth the pilot shoots a laser pulse backward at a speed of 8*10^8 meters/second with respect to the spaceship. What is the speed of the pulse as measured on earth?

Physics Questions

2. A car 3.5 m in length approaches an intersection that is 20 m wide. The light turns yellow when the car's speed is 20 m/s and the front of the car is 50 m from the beginning of the intersection. If the driver steps on the brake, the car slows at -3.8 m/s2. If he instead steps on the gas pedal, the car accelerates at 2.3 m/s2.

Acceleration, Velocity, and Speed

See attached file for full problem description. Acceleration: 1. A car goes from rest to 60 ft/sec in 30 seconds, what was its average acceleration? 2. A rocket accelerates at a rate of 200 m/sec^2 from rest for 20 seconds. What is its final velocity? 3. If the total change in velocity of an object was 50 m/sec for 10 seco

Motion - Velocity and Speed

1. Select the quantity that has changed--velocity or speed-- for a car that travels north at 88 km/h and then turns east while continuing to move at 88km/h. 2. Infer how distance and speed in the motions of clock parts are used to measure time. 3. How can you use a speedometer and a clock to tell how far you've traveled i

Speed, Time and Distance

Direction---Velocity: List the given and unknown values, perform any necessary conversions, write the equation for speed, insert the known values into the equation, and solve. 1. Find the velocity in meters per second of a swimmer who swims exactly 110 m toward the shore in 72 s. 2. Find the velocity in meters per secon

Ball's Velocity

Please see attached file for description and picture. A .3kg ball is rolling on a frictionless track, starting from rest. A) Determine at which point, (B, C, or D) the ball's velocity is maximum. B) If the ball is rolling without sliding, determine ball's velocity at point C. H= 12 meters.

Algebra - calculating velocity

If a rock is thrown upward with an initial velocity of 32 feet per second from the top of a 40-foot building, write the height equation. The formula is s = -16t^2 + v o t + s o.

Vertical Circular Motion

In an automatic clothes drier, a hollow cylinder moves the clothes on a vertical circle (radius r = 0.27 m), as the drawing shows. The appliance is designed so that the clothes tumble gently as they dry. This means that when a piece of clothing reaches an angle of above the horizontal, it loses contact with the wall of the cyli

Angular Displacement of a Baseball

A pitcher throws a curveball that reaches the catcher in 0.53 s. The ball curves because it is spinning at an average angular velocity of 335 rev/min (assumed constant) on its way to the catcher's mitt. What is the angular displacement of the baseball (in radians) as it travels from the pitcher to the catcher?

impulse applied to volleyball

A volleyball is spiked so that its incoming velocity of +3.8 m/s is changed to an outgoing velocity of -19 m/s. The mass of the volleyball is 0.38 kg. What impulse does the player apply to the ball?

The Normal Force of a Sled

A 16.5 kg sled is being pulled across a horizontal surface at a constant velocity. The pulling force has a magnitude of 85.5 N and is directed at an angle of 30.0° above the horizontal. Determine the coefficient of kinetic friction.

Physics: Velocity, Kinetic friction, Acceleration

1. Estimate the order of magnitude (exponential power) for the number of grains of salt in a salt shaker. 6. The world record for falling out of an airplane, without a parachute and surviving is 10,000m. If b is 0.13 N(s/m)^2, what is the terminal velocity of this person, assuming she has a mass of 70 kg? 9. consider pushi

Frequency of Light

The red light associated with the Aurora Borealis is emitted by excited oxygen atoms at 6.60 X 10-7 m. What is the frequency of the light? Using scientific notation, (Round your answer to two decimal places) and write the exponent part as follows: x 10 to the _ power.

Length of Time a Ball is in the Air

A baseball is propelled upward with a speed of 128 feet per second from a height of 4 feet. For how many seconds is the ball higher than 244 feet?

Circular Motion

In uniform circular motion, the acceleration is perpendicular to the velocity at every instant. Is this true when the motion is not uniform, that is, when the speed is not constant?

Circular Motion in Cycling

Dan and Beatrice cycle side by side. The tires on Dan's bike are large in diameter than those on Beatrice's bike. Which wheels, if either, have the greater rotational speed? Explain.

The Velocity of a Rocket at Parigee of an Elleptic Orbit

Problem # 4 - The rocket is traveling in a free-flight elliptical orbit about the earth such that e = 0.76 and Its perigee is 9Mm as shown. Determine its speed when it is at point B. Also determine the sudden decrease in speed the rocket must experience at A in order to travel in a Circular orbit about the earth.

Angular velocity of a sphere and cylinder on an incline

A sphere and cylinder are released from rest on the ramp at t = 0. If each has a mass m and A radius r, determine their angular velocities at time t. Assume no slipping occurs. See attached file for full problem description.

Rotational Motion of a Motor

Problem: The man stands on the platform at O and runs out toward the edge such that when he is at A, y = 5 ft, his mass center has a velocity of 2 ft/s and an acceleration of 3 ft/s^2, both measured with respect to the platform and directed along the y axis. If the platform has the angular motions shown, determine the velocity

Two Particle System in Inertial Frames, and Newtonian Relativity

See the attached file. The question starts, Consider an isolated system comprising two particles of masses m1 and m2. Whose position vectors, in an inertial frame, are x1 and x2 and whose velocity vectors are v1 and v2. The interaction of the particles may be described by an energy function. E=1/2m1v1^2+1/2m2v2^2+U(x1,x

Positve and Negative Acceleration and Velocity

1. Discuss the validity of each of the following statements. Provide examples to support the answers. a) If the acceleration of an object is positive, it is speeding up. If the acceleration of an object is negative, it is slowing down. b) If the velocity of an object is positive, it is moving away from the origin. If the vel