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# Velocity

### The Effect of Height on a Normal Force

Sarah Jane Smith rides a friction less roller coaster with an initial hill height H (on top of which the car is barely moving. At the bottom, where the track has a radius of curvature R, the car has a speed V and she feels 25% heavier than her actual weight (that is, Fn = 1.25 Fg, where Fn is the normal force the seat exerts on

### Length Contraction and Time Dilation at Small Velocities

1) The distance from New York to Los Angeles is about 5000 km and should take about 50 h in a car driving at 100 km/h. a) How much shorter than 5000 km is the distance according to the car travelers? b) How much less than 50 h do they age during the trip?

### Coriolis and Centrifugal forces - explanation

Describe the Coriolis and Centrifugal force and how to derive them. Give examples of where their effects can be seen.

### At What Height Does the Goalie Catch the Ball?

A soccer player kicks a ball so that it leaves the ground travelling 19.0 m/s at an angle of 32 degrees above the horizontal. The ball is caught by the goalie, who is standing 29.0 m down the field from where the ball was kicked. At what height does the goalie catch the ball? Also find the magnitude and direction of the ball's v

### What speed does a truck hit a tree

The driver of a truck comes suddenly upon a fallen tree that has blocked the road ahead. A total time interval of 5.45 seconds elapses during which the driver recognizes the hazard, determines the need to brake, hits the pedal, and ultimately slams into the tree. The driver's reaction time uses the first 1.25 seconds of the to

### Impulse-Momentum Theorem of a Bullet

A gun fires a bullet of mass 17 grams out of a barrel 24 cm long. The bullet is accelerated down the length of the barrel with an average force of 16 Newtons. Using the Impulse-Momentum Theorem, determine the velocity with which the bullet exits the barrel. What average force is exerted by the individual holding the gun

### A Physics Problem About Inclines

A ball starting from rest rolls 13 cm down an incline on which its acceleration is 25 cm/s2, then onto a second incline 30 cm long on which its acceleration is 7 cm/s2. How much time does it spend on each incline?

### Kinematices - Position versus Time Graphing

For each region shown below a - g, draw a section of a position versus time graph that corresponds to the regions written description (a) - (g). Assume that moving to the right is AWAY from the starting point and moving to the left is TOWARDS the starting point.

### Atomizer: air speed to draw liquid up a tube

See attached figure. # Atomizer. A sprayer consists of a tube in which moving air passes across a vertical tube to a reservoir of liquid. If the liquid has a density of 1000 kg/m3, at what speed v must the air move to draw the liquid a height of h = 10 cm up the tube? Air has a density of 1.02 kg/m3. Atomizer with air

### Determining the torque and angular velocity of a gear system

Gear 1 is driven by an electric motor and rotates at 1500 rpm clockwise. Indicate the rotating direction of each gear. Calculate: (a) the angular velocity of gear 6, (b) the gear ratio, G (c) the power and torque at input if the torque acting on gear 6, T6, is 20 Nm and the efficiency of the gear trains is 80%. See atta

### Instantaneous velocity of the object

Please help with the following problem. Please provide step by step calculations. Consider a moving object whose displacement at time t is given by s(t)=â?'5t^(2)+3t. We will take steps to find the instantaneous velocity of the object at time t=9. (a) For any time t [cannot]= 9 the average velocity of the object on

### Determining Velocity, Acceleration and Distance: Car Example

See attached file. Please provide a stepwise solution. Two cars are racing. Car A starts L=15m ahead of Car B. Car B starts with an initial velocity of v_bo=5m/s, Car A starts from rest. Car A accelerates with a_A=2m/s2, and Car B accelerates with a_B=1.5m/s2. a) Give the equations of motion for each car, assuming that

### Calculating Velocity: Cannonball Example

See attached problem. Please provide me stepwise solution. Problem 1: A cannonball is shot from cannon at the edge of a cliff (h=100), as shown in the figure below. The cannonball is shot at an angle &#952;=30°. Use the coordinate system shown for this problem. (a) The cannonball reaches a maximum height of y=30m. W

### Physics: Projectile motion for a spear in flight

A spear is thrown upward from a cliff 48 m above the ground. Given an initial speed of 24 m/s at an angle of 30º to the horizontal, a. how long is the spear in flight? b. what is the magnitude and direction of the spear's velocity just before it hits the ground?

### Kinetic energy of a body of mass; Vertical motion

22. a) A 200kg car is traveling 22 m/s. Find the kinetic energy in Joules. b) The same car is lifted vertically upward and then dropped from rest. Find the height from which it is dropped if it strikes the ground at 22 m/s (neglect air resistance). 23. In a movie, a monster climbs to the top of a building 30 m above the groun

### Speedometer Example Question

Please help me with the following question: Your car's speedometer converts the angular speed of the wheels to the linear speed of the car, assuming standard-size tires and no slipping on the pavement. A) If your car's standard tires are 24 inches in diameter, at what rate (in rpm) are your wheels rotating when you are dri

### Physics: Momentum and Collision

1. If a forward momentum of a bullet is the same as the backward momentum of the gun, why isn't it as dangerous to be hit by the gun as by the bullet? 2. Two balls are thrown at a concrete wall. both balls have the same mass and the same velocity. One ball is perfectly inelastic and stays on the wall after collision and the s

### Find the distance traveled for a given time and velocity

Under certain conditions, the velocity v (in m/s) of an object moving along a straight line as a function of the time t (in s) is given by: v= (t^2 +18T+21) / ((2t+1)*((t+4)^2)). Find the distance traveled by the object during the first 2.10 s.

A weather station releases a balloon that rises at a constant 12 m/s relative to the air, but there is a wind blowing at 7.0 m/s toward the west. What is the magnitude and direction of the velocity of the balloon?

### Vertical component of average force on ball

A bat strikes a 0.145 kg baseball. Just before impact, the ball is traveling horizontally to the right at 55.0 m/s , and it leaves the bat traveling to the left at an angle of 40 degrees above horizontal with a speed of 55.0 m/s. The ball and bat are in contact for 1.85 ms (milliseconds). Assume positive x direction is to the ri

### Vector of the current in the river

A river flows toward the east. Because of your knowledge of physics, you head your boat 38° west of north and have a velocity of 6.0 m/s due north relative to the shore. (a) What is the velocity of the current? (b) What is your speed relative to the water?

### Kinematics: Position Time graph

See attached graph. For a particle, this graph shows its displacement vs time. Discuss about the velocity and acceleration of the particle. What kind (positive, negative, constant, zero) can they be?

### Using linear kinematics to determine time and distance

1 A skier is gliding along at 2.08 m/s on horizontal, frictionless snow. He suddenly starts down a 14.2° incline. His speed at the bottom is 23.7 m/s. What is the length of the incline. 2 How long does it take him to reach the bottom?

### Mechanics - Mass, Velocity, Acceleration

1. What is the advantage of transferring masses from one side to the other instead of adding masses to one side? 2. What is the difference between uniform motion (constant velocity) and uniformly accelerated motion? 3. Why should the pulley be as light as possible and nearly frictionless?

### Velocity of the proton

A proton moving along the x axis has an initial velocity of 4.0 * 10^6 m/s and a constant acceleration of 6.0 * 10^12 m/s^2. What is the velocity of the proton after it has traveled a distance of 80 cm?

### Physics Velocity Vector

A contestant on "Survivor" is challenged to find buried treasure in a featureless desert. All the contestant knows is that she was driven away blindfolded from the treasure's location for 13 minutes with an average velocity vector having components 8.3 m/s west and 5.9 m/s north, then given a compass. She can run at a speed of 4

### Airplanes and wind velocities: Speed and direction of the plane

An airplane pilot wishes to fly due west. A wind of 88.0 km/h is blowing toward the south. a) If the airspeed of the plane (its speed in still air) is 345.0 km/h, in which direction should the pilot head? (in degrees - north of west) b) What is the speed of the plane over the ground?

### Distances and velocities: calculate time, distance and speed

The driver of a car wishes to pass a truck that is traveling at a constant speed of 19.9 m/s. Initially, the car is also traveling at a speed 19.9 m/s and its front bumper is a distance 24.0 m behind the truck's rear bumper. The car begins accelerating at a constant acceleration 0.590 m/s^2 , then pulls back into the truck's lan

### Determine the relative and absolute velocity and acceleration

Figure in the attachment shows an arrangement of a carriage system. A force P is applied on the carriage B, moving rightward at 3 m/s^2 constant acceleration. At the instant shown the velocity of B is 2 m/s. (i) Determine the velocity of B relative to A. (ii) Determine the acceleration of B relative to A. (iii) Determine th