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Fluid Pressure and force.

A 2.28 N force is applied to the plunger of a hypodermic needle. If the diameter of the plunger is 1.14 cm and that of the needle 0.215 mm, with what force does the fluid leave the needle?

Drinking Fountain Gauge Pressure

The drinking fountain outside your classroom shoots water about 16.6 cm up in the air from a nozzle of diameter 0.594 cm. The pump at the base of the unit (1.20 m below the nozzle) pushes water into a 1.20 cm diameter supply pipe that goes up to the nozzle. What gauge pressure does the pump have to provide? Ignore the viscosity;

Head-on Elastic Collision

A ball of mass 0.192 kg has a velocity of 1.52 i m/s; a ball of mass 0.302 kg has a velocity of -0.394 i m/s.They meet in a head-on elastic collision. (a) Find their velocities after the collision. m/s i (first ball) m/s i (second ball) (b) Find the velocity of their center of mass before and after the collision. m/

Basic kinematics problems: Speed, collision, displacement, velocity, degrees

? Tom is chasing Jerry across a table 1.5 m high, Jerry steps out of the way at the last second, and tom slides off the edge of the table at a speed of 5 m/s. where will tom strike the floor and what velocity components will he have just before he hits the ground. ? Two objects are initially the same height above the groun

Basic kinematic problems: Speed, velocity, degrees, distance

Please see attached files for full problem descriptions. Problem 4: The pilot of an aircraft wishes to fly due west in a wind blowing at 55 km/h toward the south. If the speed of the aircraft in the absence of wind is 179 km/h, in what direction (in degrees) should the aircraft head? Use the counter-clockwise from east conv

Mechanics: Conservation of Momentum on Variable Mass System

Sand from a stationary hopper falls onto a moving conveyor belt at the rate of 5.00 kg/s as in the figure. The conveyor belt is supported by frictionless rollers and moves at a constant speed of 0.750 m/s under the action of a constant horizontal external force Fext supplied by the motor that drives the belt. Find (a) the san

Rotational Motion: Translation and Rotational kinetic energy

(a) Without the wheels, a bicycle frame has a mass of 8.13 kg. Each of the wheels can be roughly modeled as a uniform solid disk with a mass of 0.820 kg and a radius of 0.343 m. Find the kinetic energy of the whole bicycle when it is moving forward at 3.35 m/s. K= J (b) Before the invention of a wheel turning on an axle,

Calculating Velocity Using a Position Function

Please explain how to calculate the velocity of a projectile shot upward from the surface of the earth with an initial velocity of 120 m/s after 5 seconds and after 10 seconds using a position function of s(t) = -4.9(t^2) + Vo(t) + So.

Velocity of Circular Motion

Assuming a perfectly circular orbit, how do you calculate the velocity of an object as it orbits around another object assuming for the rotating object that R=150x 10 to the six power km?

A 400 g air-track glider collides with a spring at one end of the track

I have a problem just like it in my physics book, but the mass is different. In my book it is 600 g and the answer is 0.2 s. See attached file for full problem description with diagram and units. A 400 air-track glider collides with a spring at one end of the track. The figure 1 shows the glider's velocity and the for


A hoop of 0.5 m and a mass of 0.2 kg is released from rest five meters above the horizontal and allowed to roll down an inclined plane. How fast is it moving when it is 2 meters above the horizontal?


(See attached file for full problem description and equations) --- A stone is thrown vertically upwards so that its height, measured in feet, after t seconds is given by s(t) = 100t - 16t2. What is its initial velocity? Determine the maximum height of the stone and the time of flight of the stone. ---

Linear and angular velocity.

(See attached file for full problem description with equations) --- A bullet is shot through two cardboard disks attached a distance D apart to a shaft turning with a rotational period T, as shown. (see diagram in attachment) a) Derive a formula for the bullet speed V in terms of D, T, and a measured angle between

Velocity of rocket exceeding the velocity of exhaust gas

It is possible for the velocity of a rocket to be greater than the exhaust velocity of the gases it ejects? When that is the case, the gas velocity and momentum are in the same direction as the rocket's. How does the rocket still obtain thrust by ejecting the gases?

Motion in a straight: 6 problems

1. Calculate the average speed of the Earth in its orbit about the sun. (The radius of the orbit is 1.5 x 10^11 meters.) Give this in m/s and in miles/h. Now, what is the average velocity of the earth, averaged over one year's time? 2. Is it possible for speed to be constant while acceleration is not zero? Give an example.

Leonardo da Vinci's law of motion

Leonardo da Vinci, in the fifteenth century, formulated a different law of motion. He proposed that the distances fall in successive equal intervals of time are proportional to the consecutive integers. That is, suppose that, starting from rest, a body falls one foot in the first time interval. Then the body will traverse two fe

Ballistics cart on an incline

In a demonstration known as the ballistics cart, a ball is projected vertically upward from a cart moving with constant velocity along the horizontal direction. The ball lands in the catching cup of the cart because both the cart and ball have the same horizontal component of velocity. Now consider a ballistics cart on an inclin

Mechanics Problems

How many significant numbers do each of the following numbers have? a. 214 b. 81.60 c. 7.03 d. 0.03 e. 0.0086 f. 3236 g. 8700 NOTE the 10 with a number after in () is power of ten/ scientific Notation Write the following numbers in full with the correct number of zeros. a. 8.69x10(4) b. 9.1x10(3) c. 8.8x10(-1) d.

Cross-linking a Polymer

Cross-linking a Polymer Objective The objective of this experiment is to crosslink a polymer and observes the changes in the physical properties of the polymer as a result of the crosslinking. Changes in physical properties are also sensitive to amount of crosslinking. This experiment could be expanded to investigate vario

Two-dimensional kinematics colliding cars

Two cars lost in a blinding snowstorm are traveling across a large field, each thinking they are on the road, as shown in the figure on the left. They collide. If the distance x is 124 meters and the red car is travelling at 12.7 mph, how fast to the nearest hundredth of a mph was the blue car travelling?

Simple problems on physics

1) A stone is thrown vertically upward with a speed of 18.0m/s. A.how fast is it moving when it reaches a height of 11.0m? B.how long is it required to reach this height? C.Why are there two answers to b.? 2) A falling stone takes 0.28s to travel past a window 2.2m tall. From what height above the top of

Classical Mechanics - Velocity of a bullet and a Bicyclist

A passenger at rest on a flatbed train car fires a bullet straight up. The event is viewed by observers at rest on the station platform as the train moves past the platform with constant velocity. What is the trajectory of the bullet as described by the observers on the platform? A a straight horizontal path in the directi

Finding the velocity of an electron accelerated

Question: For an accelerating voltage of 900 V calculate the time taken for an electron to reach the anode after being accelerated from rest (u=0) at the cathode of a CRT. Anode-cathode separation is 1cm. I am looking for the working's out for this problem and the answer.

Relativistic Electrons Example Problem

Two relativistic electrons are ejected simultaneously from a piece of potassium in opposite directions each is traveling with a speed of 0.5c with respect to the metal. a) what is the velocity of electron 1 with respect to electron 2? b) what is the velocity of electron 2 with respect to electron 1?

Relativistic formulas

At what velocities do the relativistic formulas for length contraction and time dilation give a 1% difference from classical values?