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Velocity

Simple harmonic motion: Position velocity and period

A raft is bobbing up and down in a lake. Its vertical position x above the flat surface of the water is given by x=0.60sin(3.0t+4.2), where distances are in metres and time t is in seconds. 1. What is the boat's position at t=0? At t=2.8s? 2. What is the period of the raft's oscillation? 3. What is the boat's maximum sp

Solid mechanics with a positive reference

See attached 1. A 2-lb ball is thrown upward at 30ft/s from an origin 5-ft above the earth's surface. Using for your positive reference a vertical Y axis with its origin at 5ft, DETERMINE FOR THE BALL: a) The maximum height in ft reached b) The elapsed time of flight in seconds until its return to the origin c) Its a

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

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

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.

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

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?

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.

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?

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.

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

S Inertial Frames

The following posting helps with problems involving inertial frames. See attached file for full problem description.

Speed of Baseball Player

A baseball player is running to second base at 5.63 m/s. When he is 5.20 m from the plate he goes into a slide. The coefficient of kinetic friction between the player and the ground is 0.220. What is his speed when he reaches the plate? 4.47 m/s 3.04 m/s 1.96 m/s He stops before reaching the plate.

Final velocity of baggage carrier

In problem 14.3(a), if the velocity of the 30 lb and 40 lb suit cases are 12 ft/s and 5 ft/s, respectively, when the first suit case of 30 lb was tossed into the carrier, the final velocity of the baggage carrier after the second baggage tossed into the carrier is: a. 4.25 ft/s b. 4.67 ft/s c. 3.87 ft/s d. 5.67 ft/s

Spring and Simple Harmonic Motion

See attached file for full problem description. 1. Gina's favorite exercise equipment at the gym consists of various springs. In one exercise, she pulls a handle grip attached to the free end of a spring to 0.80 m from its unstrained position. The other end of the spring is held in place by the equipment frame. What is the magn

Newton's 2nd Law - Kinetics

Dynamics 12.8 A car has been traveling up along a 2 percent grade at a constant speed of 55 miles/hr. If the driver does not change the setting of the throttle or shift gears as the car reaches the top of the hill, what will be the acceleration of the car as it starts moving down the 3 percent grade? Dynamics 13.7 A 24-

Orbital Mechanics

A lunar landing craft needs to hover just above the surface of the moon, which has a gravitational acceleration of (1/6) g. The exhaust velocity is 2000m/s but fuel amounting to only 20% of the total mass can be used. How long can the landing craft hover?

Energy Questions

1) Find the curl, delta x F, for the following forces: (a) F = kr; (b) F = (Ax, By2, Cz3); (c) F = (Ay2, Bx, Cz), where A, B, C and k are constants. 2) Verify that the gravitational force - GMmr/r2 on a point mass m at r, due to a fixed point mass M at the origin, is conservative and calculate the corresponding potent

Rotationial kinematics

A basketball player is balancing a spinning basketball on the tip of his finger. The angular velocity of the ball slows down from 18.5 to 14.1 rad/s. During the slow-down, the angular displacement is 85.1 rad. What is the time it takes for the ball to slow down?

Calculations with Angular Velocity

A floor polisher has a rotating disk with a radius of 15 cm. The disk rotates at a constant angular velocity of 1.4 rev/s and is covered with a soft material that does the polishing. An operator holds the polisher in one place for 45s in order to buff an especially scuffed area of the floor. How far (in meters) does a spot on th