Wednesday

August 24, 2016
**Physics**

The force between positive charges from the problem 18) has the magnitude a)4 Newtons b)9 Newtons c)9x10^9 Newtons d)4x10^9 Newtons e)none of these
*Thursday, March 5, 2015 by Vashti*

**Physics**

Two positive charges of +2 coulombs are 3 meters apart. If one of the charges is replaced by the negative charge -2 coulombs, the magnitude of force between them is: a)larger b)smaller c)the same d)zero e)none of these
*Thursday, March 5, 2015 by Vashti*

**Physics**

I need help with the second part of this question. Please show work so I can see. Thanks. I. The fastest land mammal, the cheetah, can accelerate from 0 mi/hr to 70.0 mi/hr in 3.0 seconds. What is the acceleration of the cheetah? Give your answer in units of mph/sec. I got 23....
*Thursday, March 5, 2015 by Anonymous*

**physics**

This green box, which has a mass of 500 kg, is hanging from the ceiling by two ropes. However, it's not quite centered correctly. Angle θ1=20.8 degrees and angle θ2=30.8 degrees. What is the tension in Rope # 2?
*Thursday, March 5, 2015 by Jannatul *

**Physics**

A plane traveling at 200.0 km/h attempts to land on a 250 m runway. The plane’s engines and brakes accelerate uniformly at –7.0 m/s2. Will the plane be able to land safely? Show all your work. Include any equations used, including the given and the unknown. Show all ...
*Thursday, March 5, 2015 by Vivian*

**physics**

A sled is moving at a constant speed down a surface inclined at 45.0° with the horizontal and travels 30 meters in 4 seconds. Calculate the vertical velocity of the sled at the end of 4 seconds.
*Thursday, March 5, 2015 by Anonymous*

**physics**

An inclined plane rises to aheight of 2 m over adistance of 6 m. Calculate: 1.The ange of the slope 2.The VR (and so IMA) of the inclined plane. 3The theoretical force required to push an object with a mass of 200 Kg up the slope.
*Thursday, March 5, 2015 by Yared moges*

**physics**

A child on a beach tosses a walnut straight upward. it reaches the peak of its trajectory and then falls straight downward retracing its path when a hungry seagull grabs the walnut 10.1m above the release point at a time of 1.6s after it was thrown. find the initial velocity ...
*Thursday, March 5, 2015 by Mary*

**Physics**

A mechanical device requires 420 J of work to do 230 J of work in lifting a crate. What is the efficiency of the device? I keep getting 0.5% am I right?
*Wednesday, March 4, 2015 by Anonymous*

**physics**

4.) A 8.0 kilogram physics textbook experiences an applied force of 28.0 Newtons for 2.6 seconds. The resulting acceleration is 3.50 m/s2. Determine the change in the momentum of the book.
*Wednesday, March 4, 2015 by Melissa *

**physics**

A radio station is broadcasting at 90.7 mhz. compute for its wavelength in angstrom and energy in kilojoules.
*Wednesday, March 4, 2015 by snez taba*

**Physics**

A rocket moves upward, starting from rest with an acceleration of 26.3 m/s2 for 5.43 s. It runs out of fuel at the end of the 5.43 s but does not stop. How high does it rise above the ground?
*Wednesday, March 4, 2015 by Marley*

**Physics**

Calculate the energy released when 235 U fissions resulting in two lighter stable nuclei with mass numbers 140 and 93.Please help!
*Wednesday, March 4, 2015 by William*

**Physics**

A 2.8 kg block is pushed a distance D = 9.8 meters at a constant velocity by a force F = 46 N at an angle A = 30. It takes 8.1 seconds to move the block. Friction can be ignored. What is the work done on the block by the force?
*Wednesday, March 4, 2015 by Tevin*

**Physics **

A worker applies a torque to a nut with a wrench 0.430 m long. Because of the cramped space, she must exert a force upward at an angle of 59.5° with respect to a line from the nut through the end of the wrench. If the force she exerts has magnitude 81.0 N, what magnitude ...
*Wednesday, March 4, 2015 by Reina*

**physics**

A man opens a 1.19-m wide door by pushing on it with a force of 54.5 N directed perpendicular to its surface. (a) What magnitude torque does he apply about an axis through the hinges if the force is applied at the center of the door? ___N · m (b) What magnitude torque ...
*Wednesday, March 4, 2015 by Reina*

**Physics **

A construction crane's cable lifts a 59.5-kg box upward with an acceleration of 1.38 m/s^2. Find the tension in the rope. 501.585 is incorrect.
*Wednesday, March 4, 2015 by Reina*

**physics**

Find the net torque on the wheel in the figure below about the axle through O perpendicular to the page, taking a = 5.00 cm and b = 23.0 cm. (Indicate the direction with the sign of your answer. Assume that the positive direction is counterclockwise.) f1= 10 f2= 9 f3=12
*Wednesday, March 4, 2015 by alba*

**physics**

a bus is travelling on a horizontal road at a velocity of 126 km/h when the bus driver notices an object in the road. the brakes are applied and the bus is brought to rest over a distance of 150m. the frictional resistance is 2500n and the bus has a mass of 6000 kg. calculate ...
*Wednesday, March 4, 2015 by Enoch*

**Physics**

3. Think about this pulling scenario: A 60 N force pulls three boxes across a surface with no friction. T1 is the tension force the rope on the left pulls with at both ends, and T2 is the force the rope on the right pulls with on both ends. (a) Draw diagrams of the three boxes...
*Wednesday, March 4, 2015 by Ke*

**physics**

7. A cart like the one we use in lab accelerates down a 20° incline (and since the wheels are smooth, ignore friction for now). Break the force of gravity into components (leave mass as m for now), find the cart’s acceleration, and determine how long it should take ...
*Wednesday, March 4, 2015 by Ke*

**physics**

a parent pushes a kid on a swing, A) If the child on the swing rises 2m above the lowest point during each cycle, what is her speed at the lowest point of the swing? B)If the beginning of a cycle (2m above the lowest point) the child is given a push so that her starting speed ...
*Wednesday, March 4, 2015 by chris*

**Physics**

A driver of a car going 90 km/h suddenly sees the lights of a barrier 40.0 m ahead. It takes the driver 0.75 s to apply the brakes, and the average acceleration during braking is -10 m/s2. (a) Compute for the total displacement of the car to determine whether the car hits the ...
*Wednesday, March 4, 2015 by Leila*

**Calculus Physics**

A glass of orange juice is on the floor of a subway car traveling along a straight path at constant velocity. Everything's fine. The coefficient of static friction between the glass and the floor is 0.32. The subway suddenly accelerates forward. What is the maximum ...
*Wednesday, March 4, 2015 by Mik*

**Physics**

A baseball player with a mass of 79 kg slides into homeplate. The coefficient of kinetic friction between the player and the ground is μk = 0.632. If the player comes to rest after 1.04 s, what is his initial speed?
*Wednesday, March 4, 2015 by danny*

**physics**

In a relay race, each contestant runs a distance 25.7m while carrying an egg balanced on a spoon, turns around, and comes back to the starting point. Jenny runs the first distance 25.7m in a time t1 = 20.0s . On the return trip she is more confident and takes only time t2 = 14...
*Wednesday, March 4, 2015 by Kikobay*

**Physics**

Energy Budget for a Rocket in Free Space: Recall the analysis of the rocket engine in Project I, Flight of the Rocket. Although the momentum of the rocket and its exhaust is conserved (constant), their energy is not; energy must be supplied by the combustion of fuel. WARNING: ...
*Wednesday, March 4, 2015 by Steve*

**Physics**

Bob starts spinning his hammer at a rate of 2.00 rad/s^2. At the same time, he starts running towards Jim at 4.00 m/s^2. The distance from the end of the hammer to Bob's elbow is 1.20 m. If Bob takes 3 seconds before he launches the hammer at Jim, what is the resultant ...
*Wednesday, March 4, 2015 by Lisa*

**physics **

Before starting this problem, review Conceptual Example 7. The force vector A has a magnitude of 97.0 newtons (N) and points due east. The force vector B has a magnitude of 107 N and points 71.4 ° north of east. Find the (a) magnitude and (b) direction of A - B. (Give the...
*Wednesday, March 4, 2015 by n *

**Physics **

A .5 kg football is thrown and reaches a stationary receiver with a speed of 15m/s. The receiver catches the ball and brings it to rest in .2 sec. a) What is the impulse delivered to the ball? b) What is the average force exerted on the receiver?
*Wednesday, March 4, 2015 by Rachel*

**Physics**

Starting from rest, a 4-kg block slides 10 m down a frictionless 30 degree incline. Determine the work done on the block by a) The force of gravity b) The normal force c) All of the forces (the net force) on the block d) Find the Kinetic energy of the block at the end of the ...
*Wednesday, March 4, 2015 by Rachel*

**Physics**

Please help me with this question How much work is done by a boy of mass 70kg who ran up a flight of 31steps each15m high. Take g=10m/s^2
*Wednesday, March 4, 2015 by Cassandra*

**Physics**

A square coil with 30 turns has sides that are 18 cm long. When it is placed in a 0.31-T magnetic field, a maximum torque of 0.60 N⋅m is exerted on the coil. What is the current in the coil?
*Tuesday, March 3, 2015 by Keith*

**Physics**

Energy Budget for a Rocket in Free Space: Recall the analysis of the rocket engine in Project I, Flight of the Rocket. Although the momentum of the rocket and its exhaust is conserved (constant), their energy is not; energy must be supplied by the combustion of fuel. WARNING: ...
*Tuesday, March 3, 2015 by Steve*

**physics**

A 4 cm candle sits 15 cm in front of a converging lens with a focal length of 6.0 cm. Draw a ray diagram showing the image used and determine the image distance and magnification. Please help me answer!
*Tuesday, March 3, 2015 by sarah*

**Physics**

A 39-turn circular coil of radius 3.20 cm and resistance 1.00 Ω is placed in a magnetic field directed perpendicular to the plane of the coil. The magnitude of the magnetic field varies in time according to the expression B = 0.010 0t + 0.040 0t2, where B is in teslas and...
*Tuesday, March 3, 2015 by Chris*

**Physics**

Can someone help me solve this one? I've tried it a few times, but I don't think I'm getting it right. A block of mass M = 2.2 kg starts from rest at a height of 3.6 m on a fixed inclined plane. The coefficient of kinetic friction between the block and the incline ...
*Tuesday, March 3, 2015 by James*

**Physics**

Can someone walk me through how to work this? It's worded weirdly and I'm not sure how to solve it. Mass M1= 2.2 kg lies on a frictionless table, pulled by another mass M2= 4.1 kg under the in of Earth's gravity. a) What is in N the net force acting on the system ...
*Tuesday, March 3, 2015 by James*

**Physics**

Can someone walk me through how to work this? A block is being pushed up a frictionless incline by an applied horizontal force, F=12.7N. (The angle is θ = 23.80° and the mass is 1.70kg. a) How many forces are acting on the block? b) How many of those forces are along ...
*Tuesday, March 3, 2015 by James*

**physics**

A constant torque of 200Nm turns a wheel about its centre. The moment of inertia about this axis is 100kgm^2
*Tuesday, March 3, 2015 by ben*

**Physics **

A cannon shoots a cannonball with a mass of 20 kg and a net force of 2000 N a) label the three force pairs(HORIZONTAL ONLY) b) What is the acceleration of the cannonball? c) Does the cannon continue to move/ Explain why or why not. Specify which force will affect this.
*Tuesday, March 3, 2015 by Nam Nguyen*

**physics**

Object 1 has a velocity of 3m/s and a mass of 5kg. Object 2 also has a mass of 5kg but isn't moving. Object 1 collides with Object 2 and they move off together. Work out their speed using the principle of conservation of momentum.
*Tuesday, March 3, 2015 by help me *

**physics**

a stone is thrown upward with a speed of 24.0m/s how fast is it moving when it reaches a height of 13.0m?
*Tuesday, March 3, 2015 by oratile*

**Physics**

Consider an air-bubble level that is sitting on a horizontal surface. Initially, the air bubble is in the middle of the horizontal glass tube. (a) If the level is pushed and a force is applied to accelerate it, which way would the bubble move? Which way would the bubble move ...
*Tuesday, March 3, 2015 by David*

**Physics**

A 1500-kg blue car is travelling south, and a 2000-kg red sports car is travelling west. If the momentum of the system consisting of the two cars is 8000kg.m/s directed at 60 degrees west of south, what is the speed of each car?
*Tuesday, March 3, 2015 by Reynaldo*

**Physics**

A 100 kg crate rest at the back of the bed of a pick up truck. The length of the crate is 1 m in the length of the bed is 4 m. There is no friction between the bed of the truck in the crate. If the truck is traveling at 25 m/s just before it hits the wall, how long before the ...
*Tuesday, March 3, 2015 by David*

**Physics**

a billiard ball moving at 4.0 m/s strikes another billiard ball at rest and moves off at 3.46 m/s in a direction of 30 degrees from the original of the motion. What is the velocity of the target ball?
*Tuesday, March 3, 2015 by Reynaldo*

**physics**

The weight of an object is 480N on the earth and 120N on the moon,calculate the mass of the object on the moon
*Tuesday, March 3, 2015 by rebone*

**physics**

If a man weighs 820N on d earth what would be on Jupiter, where the acceleration due to gravity is 25.9m/s
*Tuesday, March 3, 2015 by ikeokwu stephen chidebere*

**Physics**

A chair of weight 75.0N lies atop a horizontal floor; the floor is not frictionless. You push on the chair with a force of F = 45.0N directed at an angle of 40.0¡ã below the horizontal and the chair slides along the floor. Using Newton's laws, calculate n, the...
*Tuesday, March 3, 2015 by Boxiang*

**physics**

An object uniformly accelerates at a rate of 1.20m/s^2 east. While accelerating at this rate, the object is displaced 470.4m east in a time of 28 s. What velocity did this object reach in this time ? I used Vf=Vi+at which will be Vf=(1.20)(28) but i feel this isn't the way...
*Tuesday, March 3, 2015 by Dania *

**Physics**

A 4.12 kg mass undergoes an acceleration along both the x and y directions. Ax = -2.60 m/s2 and Ay = 3.50 m/s2. Find the magnitude of the resultant force. Answer in units of N.
*Monday, March 2, 2015 by Joey*

**physics**

Jane and John, with masses of 50kg and 68kg , respectively, stand on a frictionless surface 13m apart. John pulls on a rope that connects him to Jane, giving Jane an acceleration of 0.86m/s2 toward him. What is the magnitude of the John's acceleration? If the pulling force...
*Monday, March 2, 2015 by Herb*

**college physics**

A fisherman poles a boat as he searches for his next catch. He pushes parallel to the length of the light pole, exerting a force of 245 on the bottom of a shallow lake. The pole lies in the vertical plane containing the boat's keel. At one moment, the pole makes an angle ...
*Monday, March 2, 2015 by molly*

**physics**

An atomic nucleus at rest decays radioactively into an alpha particle and a different nucleus.
*Monday, March 2, 2015 by Anonymous*

**physics**

NEEDS HELP PLEASE!! A 100kg shot putter is putting a shot 4kg. Just before he releases the shot, he is in the air (feet are off the ground). At this instant, the only force he exerts against the shot is an 800N horizontal force directed forward. a-what is his horizontal ...
*Monday, March 2, 2015 by sam*

**physics**

A negatively charged balloon has 4.5 μC of charge. How many excess electrons are on this bal- loon? The elemental charge is 1.6 × 10−19 C. Answer in units of electrons.
*Monday, March 2, 2015 by Anonymous*

**physics**

A 4.40kg bucket of water is accelerated upward by a cord of negligible mass whose breaking strength is 74.0N
*Monday, March 2, 2015 by AHMED*

**Calculus Physics**

Imagine a spaceship on its way to the moon from the earth. Find the point, as measured from the center of the earth, where the force of gravity due to the earth is balanced exactly by the gravity of the moon. This point lies on a line between the centers of the earth and the ...
*Monday, March 2, 2015 by danny*

**Calculus Physics**

A glass of orange juice is on the floor of a subway car traveling along a straight path at constant velocity. Everything's fine. The coefficient of static friction between the glass and the floor is 0.32. The subway suddenly accelerates forward. What is the maximum ...
*Monday, March 2, 2015 by danny*

**Physics**

Analyze the flight of a projectile moving under the influence of gravity (mg) and linear, i.e., laminar- flow drag (fD = bv, with b > 0 constant). Neglect \Phase I"; assume the projectile is launched from the origin at speed v1 and angle 1 above the horizontal. WARNING...
*Monday, March 2, 2015 by Alyssa*

**Physics**

A 100kg object moving at 20 m/s comes to a stop over distance of 40 m. What is the coefficient of dynamic fiction between the object and the ground? I tried to work it out with the formula, but I'm really confused. Please help.
*Monday, March 2, 2015 by Mary*

**physics**

The largest tension that can be sustained by a stretched string of linear mass density μ, even in principle, is given by τ = μc2, where c is the speed of light in vacuum. (This is an enormous value. The breaking tensions of all ordinary materials are about 12 ...
*Monday, March 2, 2015 by barış*

**Physics **

An outdoor swimming pool contains 100000 kilogram of water how much energy is needed yo heat water from 15 celius to 20 celius
*Monday, March 2, 2015 by Anonymous*

**physics**

Heat can never flow from ________. how come it is cold to hot?
*Monday, March 2, 2015 by Sabina*

**Basic Physics**

There is a rocket on a stage connected a spring with the spring constant k(N/m). The weights of the rocket and the stage are m(kg) and M(kg), respectively. The length of the spring without the stage and rocket or free is h0(m) and it becomes shrunk to h(m) on putting the ...
*Monday, March 2, 2015 by Sarwar*

**help! Physics**

I've been getting this question wrong so many times! What is the relationship between the coefficient of friction and the time that it takes the object to reach the bottom of the ramp?
*Monday, March 2, 2015 by Stephanie*

**modern physics**

a hunter on the ground fires a bullet in the northeast direction which strikes a deer 0.25 metre away from him, the bullet travel with a speed of 1800m/hr.at the instant an airplane is directly over the hunter at an altitude of one metre and is traveling due east with a ...
*Sunday, March 1, 2015 by martin*

**Physics**

A baseball pitcher delivers a fastball that crosses the plate with an angle of 7.89 degrees relative to the horizontal and a speed of 87.5 mph. The ball (mass 0.145 kg) is hit back over the head of the pitcher at an angle of 38.03 degrees with respect to the horizontal and a ...
*Sunday, March 1, 2015 by Kathy*

**physics **

A seesaw has a mass of 30 kg, a length of 3.0 m, and fulcrum beneath its midpoint. It is balanced when a 50-kg person sits on one end and a 65-kg person sits on the other end.Locate the center of mass of the seesaw (a distance from the 50-kg person)
*Sunday, March 1, 2015 by clay *

**physics**

A particle moves half distance by 20 m/s and stay half distance moves by 30 m/s. Average speed of total journey should be?
*Sunday, March 1, 2015 by Pradeep*

**Physics**

A 7.5 kg box is on a table. What is the normal force acting on the box in each of the following situations? a) You leave the box alone. b) You push down on the box with a force if 20 N. c) You pull up on the box with a force of 20 N.
*Sunday, March 1, 2015 by Ashley*

**Physics**

A top is a toy that is made to spin on its pointed end by pulling on a string wrapped around the body of the top. The string has a length of 80 cm and is wound around the top at a spot where its radius is 2.0 cm. The thickness of the string is negligible. The top is initially ...
*Sunday, March 1, 2015 by Cass*

**Physics**

A worker pushes horizontally on a 25 kg crate resting on ground level. The coefficients of static and kinetic friction are 0.4 and 0.3.? a) How much force must he apply to start the crate moving? b) After the crate has stereo moving, how much force must he apply to move the ...
*Sunday, March 1, 2015 by Ashley*

**Physics**

A 24.8-g bullet is fired from a rifle. It takes 2.15 × 10-3 s for the bullet to travel the length of the barrel, and it exits the barrel with a speed of 778 m/s. Assuming that the acceleration of the bullet is constant, find the average net force exerted on the bullet.
*Sunday, March 1, 2015 by Chris*

**Physics**

The brakes of a truck cause it to slow down by applying a retarding force of 7760 N to the truck over a distance of 870 m. What is the work done by this force on the truck?
*Sunday, March 1, 2015 by Chris*

**physics**

A 100kg shot putter is putting a shot 4kg. Just before he releases the shot, he is in the air (feet are off the ground). At this instant, the only force he exerts against the shot is an 800N horizontal force directed forward. a-what is his horizontal acceleration at this ...
*Sunday, March 1, 2015 by aaron*

**physics**

a jeepney from rest accelerates unit fromly covers the time 3.25s. and covers in 15m. Determine the acxeleration of jeepney
*Sunday, March 1, 2015 by azihr*

**Physics**

There is an 8 meter tall hill with a circular radius of 20 meters. What is yhe minimum speed a car needs to momentarily lose contact with the road?
*Sunday, March 1, 2015 by Valerie *

**Physics**

What is the final temperature reached by the addition of 11.4 grams of steam at 100C to 681 grams water at 25C in an aluminum calorimeter having a mass of 781 grams? C of water=1 cal/gc C of aluminum= 0.22 cal/gc L steam= 540cal/g My Attempt Qloss=Qgain Qst+Qhw=Qcup+Qcw ml+mcT...
*Sunday, March 1, 2015 by Help2*

**physics**

Grant accelerates a 1kg ball 5.0m/s2 horizontally. The vertical acceleration of the ball is zero. The force of gravity is the only external force acting on the ball other than the forces Grant exerts on it. a-How large is the horizontal force grant exerts on the ball at this ...
*Sunday, March 1, 2015 by aaron*

**Physics**

An unstable nucleus with a mass of 18.0 ✕ 10-27 kg initially at rest disintegrates into three particles. One of the particles, of mass 4.1 ✕ 10-27 kg, moves along the positive y-axis with a speed of 8.0 ✕ 106 m/s. Another particle, of mass 7.7 ✕ 10-...
*Sunday, March 1, 2015 by Betty*

**Physics 1**

In recent years, scientists have discovered hundreds of planets orbiting other stars. Some of these planets are in orbits that are similar to that of earth, which orbits the sun (Msun = 1.99 × 10^(30) kg) at a distance of 1.50 × 10^(11) m, called 1 astronomical ...
*Sunday, March 1, 2015 by Skyler*

**physics(urgent answer pls)**

A projectile is launched with 30m/s at an angle of 60degree with d horizontal (a) find d position of the projectile,and d magnitude and direction of its velocity at t=2s (b) find d time when d ball reaches the highest point (c) find d horizontal range
*Sunday, March 1, 2015 by ben*

**physics**

A projectile is launched with 30m/s at an angle of 60degree with d horizontal (a) find d position of the projectile,and d magnitude and direction of its velocity at t=2s (b) find d time when d ball reaches the highest point (c) find d horizontal range
*Sunday, March 1, 2015 by tolu*

**Physics**

A group of soldiers hid at the bottom and against the wall of a 100 m. high cliff. Unknown to them, the Evil rebels have positioned a cannon on top of the cliff; 8,000 m. from the edge. If the cannon has a muzzle speed of 320 m/sec, how close to the bottom edge of the cliff ...
*Sunday, March 1, 2015 by akocciara*

**physics**

a block of ice slides down a 45degree inclined plane in twice the time it takes to slide down a 45degree frictionless inclined plane. what is the coefficient of kinetic friction between the ice block and the plane?
*Sunday, March 1, 2015 by ogba*

**physics**

a block of ice slides down a 45degree inclined plane in twice the time it takes to slide down a 45degree frictionless inclined plane. what is the coefficient of kinetic friction between the ice block and the plane?
*Sunday, March 1, 2015 by Anonymous*

**physics **

A car has a uniform velocity of 108km/h. How far does it travel in 1/2 min
*Sunday, March 1, 2015 by Godspower*

**physics**

Why do you think the wave aspect of light was discovered earlier than its particle aspect?
*Sunday, March 1, 2015 by Channing*

**physics**

A bug starts walking away from the top of a spherical ball of ice and will start to slip when the normal force exerted on it drops to 1/2 of its weight. If the ice ball has a diameter of 34 cm, how far can the bug walk before it begins to slip?
*Sunday, March 1, 2015 by wayne*

**Physics**

A model helicopter and its load have a combined mass of 3.5 kg. Find the upward average force, in Newtons, exerted by the air if the helicopter is originally moving downward at 10 m/s and is brought to rest with constant acceleration in a distance of 50 m.
*Sunday, March 1, 2015 by wayne*

**Physics**

Three cylindrical blocks x, y and z are made of different materials of densities 2g/cm3, 5g/cm3 and 10g/cm3 respectively. If the side of each block resting on a level surface has an area of 2cm2, 4cm2 and 6cm2 and the height of block x is 10cm calculate; 1) weight of block x 2...
*Saturday, February 28, 2015 by JUBA*

**Physics**

A 4.1 g dart is fired into a block of wood with a mass of 20.2 g. The wood block is initially at rest on a 1.2 m tall post. After the collision, the wood block and dart land 2.6 m from the base of the post. Find the initial speed of the dart.
*Saturday, February 28, 2015 by Betty*

**Physics**

An unstable nucleus with a mass of 18.0 ✕ 10-27 kg initially at rest disintegrates into three particles. One of the particles, of mass 4.1 ✕ 10-27 kg, moves along the positive y-axis with a speed of 8.0 ✕ 106 m/s. Another particle, of mass 7.7 ✕ 10-...
*Saturday, February 28, 2015 by Carol*

**physics**

A 2200 kg car traveling at 8.7 m/s collides with a 2750 kg car that is initially at rest at the stoplight. The cars stick together and move 2.00 m before friction causes them to stop. Determine the coefficient of kinetic friction between the cars and the road, assuming that ...
*Saturday, February 28, 2015 by Amy*

**physics**

A 39-turn circular coil of wire has a diameter of 1.2m. It is placed with its axis along the direction of the Earth's magnetic field of 58μT at 52° below the horizontal, and then in 0.16s it is flipped 180°. a) What is volts the magnitude of the average ...
*Saturday, February 28, 2015 by Katie*

**physics**

a rectangular loop with a=6.0 cm, and b=4.0 cm, moving with a velocity v=8.0 cm/s into an area where the magnetic field is uniform, pointing into the page, and whose magnitude is B= 440 mT. a) What is in volts the induced emf in the loop when the loop is moving in a region ...
*Saturday, February 28, 2015 by Ciel*

**physics**

A 3.49 kg mud ball has a perfectly inelastic collision with a second mud ball that is initially at rest. The composite system moves with a speed equal to one-seventh the original speed of the 3.49 mud ball. What is the mass of the second mud ball?
*Saturday, February 28, 2015 by Amy*

**Physics**

Two boats are heading away from shore. Boat 1 heads due north at a speed of 4 m/s relative to the shore. Relative to boat 1, boat 2 is moving 35° north of east at a speed of 1.2 m/s. A passenger on boat 2 walks due east across the deck at a speed of 1.3 m/s relative to ...
*Saturday, February 28, 2015 by Cetris*