Number of results: 47
A car starts from rest on a curve with a radius of 160 m and accelerates at 1.80 m/s^2. How many revolutions will the car have gone through when the magnitude of its total acceleration is 2.20 m/s^2?
October 11, 2009 by Amanda
What is the spring constant of a spring that stretches 2.00 cm when a mass of 0.600 kg is suspended from it? Answer i know the answer is 295 n/m but im nto sure how they got to it,
January 15, 2013 by v
phyiscs repost 2
Calculate the sound level in decibels of a sound wave that has an intensity of 2.25 µW/m2 For this question don't I use B=log10(I/IO) So it would be B=log10(2.25/1.0e-12) right?
April 19, 2008 by chris adison
A stone is thrown horizontaly from the top of a 25.00-m cliff. The stone lands at a distance of 40.00 m from the edge of the cliff. What is the horizontal velocity of the stone?
October 22, 2010 by ashlee
A hollow copper tube (diameter = 4.01 cm) is sealed at one end and loaded with lead shot to give a total mass of 0.218 kg. When the tube is floated in pure water, what is the depth, z, of its bottom end?
April 3, 2014 by Jason
Many kayaks are made of plastics and other composite materials that are denser than water. How are such kayaks able to float in water? Does the kayak displace water? What exactly is Archimedes's Principle?
May 8, 2007 by Anonymous
A man claims he can safely hold on to a 9.7-kg child in a head-on collision with a relative speed of 112-mi/h lasting for 0.12 s as long as he has his seat belt on. (a) Find the magnitude of the average force needed to hold onto the child. HELP
November 25, 2009 by Rick
A bolt is dropped from a bridge under construction, falling 81 m to the valley below the bridge. (a) How much time does it take to pass through the last 28 % of its fall? What is its speed (b) when it begins that last 28 % of its fall and (c) just before it reaches the ground?
September 12, 2013 by kristy
Why is an antenna designed to be one-half of the wavelength of the wave it is supposed to receive? In my book all it says is that the voltage is larger when the antenna is 1/2 the wavelength of the wave.
May 29, 2009 by sally
A rock is tossed straight up with a velocity of 33.9 m/s. When it returns, it falls into a hole 11.9 m deep. What is the rock's velocity as it hits the bottom of the hole?
October 4, 2010 by Em
The height of a helicopter above the ground is given by h = 2.90t3, where h is in meters and t is in seconds. At t = 1.75 s, the helicopter releases a small mailbag. How long after its release does the mailbag reach the ground?
September 19, 2011 by fayez
A uniform plank of length 4.5 m and weight 233 N rests horizontally on two supports, with 1.1 m of the plank hanging over the right support (see the drawing). To what distance x can a person who weighs 454 N walk on the overhanging part of the plank before it just begins to tip?
November 19, 2010 by jason
A 5.00g lead bullet is fired into a wooden fence post. The initial speed of the bullet is 250m/s, and when it comes to rest, half its kinetic energy goes into heating bullet. How much does the bullet's temperature increase?
November 25, 2012 by noname
Two persons watch the same object move john says that it accelerate straight downward, but Samantha claims that it falls Along curved path.describe the conditions under which each person would be reporting correctly what they see. Thanks and please please please answer this ...
April 1, 2011 by tim
A woman is standing on the middle of a ladder that leans up against a building, with an angle of 65 degrees from the ground. The wall is very slippery and the ladder is very light. What is the minimum coefficient of friction needed between the ground and the ladder so that the...
April 27, 2011 by Anonymous
A satellite circles the earth in an orbit whose radius is 2.07 times the earth's radius. The earth's mass is 5.98 x 1024 kg, and its radius is 6.38 x 106 m. What is the period of the satellite?
June 30, 2013 by Justin S.
True or false: When a system consists of several objects, each with their own mass and velocity, the linear momentum of the system as a whole is simply the product of the system's total mass and the velocity of the system's center of mass.
October 30, 2012 by Angelena
1 more phyiscs for today
sorry for asking for help agen. a baseball catcher puts on an exhibition by catching a .150kg ball dropped from a helicopter at a height of 100m above the catcher. if the catcher "gives with the ball for a distance of .75m while catching it, what average force is exerted on ...
November 6, 2008 by joyce
Having landed on a newly discovered planet, an astronaut sets up a simple pendulum of length 1.51 m and finds that it makes 291 complete oscillations in 697 s. The amplitude of the oscillations is very small compared to the pendulum’s length. What is the gravitational ...
November 16, 2011 by amanda
phyiscs- rube goldberg machine
Identify two types of simple machines that are included in a Rube Goldberg machine. Pick any simple machines: For example, wedge, and lever.
January 13, 2007 by Anonymous
A teenager accidentally falls off a 10 m high platform diving board. His friend whips out his camera and takes a picture when the teenager is halfway to the water below to commemorate the embarrassing event and post it on Facebook. How many seconds after the teenager fell off ...
April 2, 2013 by Anyone....out...help..please!!!
Phyiscs - Electro static
Particles 1 and 2 of charge q1 = q2 = +3.20 x 10-19 C are on a y axis at distance d = 22.0 cm from the origin. Particle 3 of charge q3 = +9.60 x 10-19 C is moved gradually along the x axis from x = 0 to x = +5.0 m. At what value of x will the magnitude of the electrostatic ...
April 2, 2011 by will
Phyiscs help 3
The height of a tower is measured by attaching a simple pendulum to its ceiling, whose length is barely enough to stay off the floor. The pendulum is let go from a small angle, and takes 13 s to return to the same location it started from. a.) How tall is the tower? ? m If the...
November 9, 2008 by kelsey
A stone falls from a railroad overpass which is 36 ft high into the path of a train which is approaching the overpass with a uniform speed. If the stone falls when the train is 50 ft away from the overpass and the stone hits the ground just as the train arrives at that spot, ...
September 5, 2011 by Stone
A paratrooper fell 380m from an airplane without being able to open his chute but happened to land in snow, suffering only minor injuries. Assume that his speed at impact was 58 m/s(terminal speed), that his mass (including gear) was 90 kg, and that the force on him from teh ...
January 12, 2008 by Kristen
A lbock is given an intial speed of 4.0 s^-1 m up the 22 degree plane How far up the plane will it go ok I got this to be something like 2.2 about i understand this i need help on this how much time elapses before it returns to tis starting point? Ignore friction. ok I need to...
July 11, 2009 by Physics
Suppose you throw a stone straight up with an initial velocity of 27.0 m/s and, 5.5 s later you throw a second stone straight up with the same initial velocity. The first stone going down will meet the second stone going up. At what height above the point of release do the two...
December 5, 2012 by HENRY!
An escalator in a shopping centre carries people up through a height h at a vertical speed of v, but you’re in a hurry when you step onto it, so you climb the moving steps (each with a height of h ) at a rate of n steps/s. Determine: 4.1 the amount of chemical energy converted...
April 22, 2014 by Debby
How do I do these? Draw a free-body diagram for each of the following objects? a. a projectile in motion in the presence of air resistance b. a rocket leaving the launch pad with its engines operating c. a heavy crate being pushed across a rough surface a. mg is down, Ff is ...
December 5, 2006 by Anonymous
A bicyclist makes a trip that consists of three parts, each in the same direction (due north) along a straight road. During the first part, she rides for 22 minutes at an average speed of 6.80 m/s. During the second part, she rides for 36 minutes at an average speed of 5.20 m...
October 5, 2010 by Ash
phyiscs help please
A 3.00*10^2 N force is pulling an 80.0 kg refrigerator across a horizontal surface. The force acts at an angle of 18.0° above the surface. The coefficient of kinetic friction is 0.200, and the refrigerator moves a distance of 8.00 m. (a) Find the work done by the pulling force...
October 29, 2010 by Anonymous
Please show work You decide to take a nice hot bath but discover that your thoughtless roommate has used up most of the hot water. You fill the tub with 270 kg of 30.0°C water and attempt to warm it further by pouring in 5.00 kg of boiling water from the stove. (a) Is this a ...
July 15, 2010 by Anonymous
A wooden box with a mass of 10.0kg rests on a ramp that is inclined at angle of 25 degrees to the horizontal. A rope attached to the box runs parallel to the ramp and then passes over a frictionless pulley. A bucket with a mass of m hangs from the end of the rope. The ...
February 6, 2014 by Lupita
Phyiscs - due at 11PM EST!!
Two identical conducting spheres, fixed in place, attract each other with a force of 0.114 N when their center to center separation is 45.00 cm. The spheres are then connected by a thin conducting wire. When the wire is removed, the spheres have a net positive charge and repel...
April 12, 2011 by Bill
A bowler throws a bowling ball of radius R=11 cm down a lane. The ball slides on the lane, with initial speed v(of the center of mass)=7 m/s and initial angular speed =0. The coefficient of kinetic friction between the ball and the lane is .25. The kinectic frictional force fk...
February 10, 2008 by kristen