A 45 kilogram bicyclist on a 5 kilogram bicycle rides down a 50 meter high hill with her brakes partially on. Her speed at the bottom of the hill is 10 meters per second. How many kilojoules of heat were dissipated by the cyclist's brakes?

1 Answer

Answer :

ANSWER: 22.5 KILOJOULES or 22.0 KILOJOULES (based on 9.8 m/s2)

Related questions

Description : A 50 kilogram ice skater glides across the ice in a straight line at 7 meters per second. If she bends down and scoops up a 20 kilogram child standing on the ice, what will be the final speed of the skater ... w) 1 meter per second x) 3 meters per second y) 5 meters per second z) 7 meters per second

Last Answer : ANSWER: Y -- 5 METERS PER SECOND

Description : An impulse of 10 kilogram-meter per second acting on an object whose mass is 5 kilogram will cause a change in the objects velocity of: w) 0.5 meters per second x) 2 meters per second y) 10 meters per second z) 50 meters per second

Last Answer : ANSWER: X -- 2 METERS PER SECOND

Description : A kilogram of water goes from 90 degrees Celsius to 10 degrees Celsius in a period of 2 hours. If the specific heat of water is 4 kilojoules per kilogram per degree Celsius, how much heat has the water lost?

Last Answer : ANSWER: 320 KILOJOULES or 320,000 JOULES

Description : A boy on a bicycle is resting at the top of a hill. Then, he rides his bicycle down the hill. Describe how the boy’s potential and kinetic energy differ at the top, middle, and bottom of the hill.?

Last Answer : idk

Description : An 8 kilogram mass resting on a frictionless horizontal surface is attached to a spring with a force constant of 50 Newtons per meter. If the velocity of the mass through the equilibrium position is 5 meters per second, what is the mass's maximum displacement from equilibrium?

Last Answer : ANSWER: 2 METERS

Description : A car with a mass of 1000 kilogram is moving at a speed of 10 meters per second. The kinetic energy of the car is: w) 100 Joules x) 5000 Joules y) 10,000 Joules z) 50,000 Joules

Last Answer : ANSWER: Z -- 50,000 JOULES

Description : A 10 kilogram mass rests on a horizontal frictionless surface. A horizontal force of 5 Newtons is applied to the mass. After the force has been applied for 1 second, the velocity of the mass is: w) 0 meters per second x) 0.5 meters per second y) 5 meters per second z) 50 meters per second

Last Answer : ANSWER: X -- 0.5 METERS PER SECOND

Description : As a 10 kilogram mass on the end of a spring passes through its equilibrium position, the kinetic energy of the mass is 20 joules. The speed of the mass is: w) 2.0 meters per second x) 4.0 meters per second y) 5.0 meters per second z) 6.3 meters per second

Last Answer : ANSWER: W -- 2.0 METERS PER SECOND

Description : A car is moving along a straight horizontal road at a speed of 20 meters per second. The brakes are applied and a constant force of 5000 Newtons decelerates the car to a stop in 10 seconds. The mass of the car is: w) 1250 kilograms x) 2500 kilograms y) 5000 kilograms z) 10,000 kilograms

Last Answer : ANSWER: X -- 2500 KILOGRAMS

Description : A two-stage rocket attains a velocity of 3,000 meters per second when it drops the first stage and ignites the second. It consumes 1 kilogram of fuel per second and its exhaust speed is 2,000 meters per second. ... ? w) 2,000 Newtons x) 3,000 Newtons y) 2,000 Newton-seconds z) 3,000 Newton-seconds 

Last Answer : ANSWER: W -- 2,000 NEWTONS

Description : A man picks up a 50 kilogram block and carries it up a flight of stairs 10 meters high. He then carries the block back down the stairs and places the block in its original position. What is the NET work done on the block? w) 1,000 joules x) 750 joules y) 500 joules z) 0 joules

Last Answer : ANSWER: Z -- 0 JOULES

Description : What is the DeBroglie wavelength of a 1,200 kilogram corvette traveling at a rate of 25 meters per second? Planck's constant is equal to 6.62 x 10-34 Joule-seconds. w) 5.3 x 10-32 meters x) 5.9 x 10-34 meters y) 2.1 x 10-38 meters z) 1.6 x 10-40 meters

Last Answer : ANSWER: Y -- 2.1 x 10-38 METERS

Description : A 500 kilogram car moving at 20 meters per second strikes a stone wall and is brought to a halt in 0.1 second. The average force of the car on the wall during impact is: w) 10 Newtons x) 1000 Newtons y) 10,000 Newtons z) 100,000 Newtons

Last Answer : ANSWER: Z -- 100,000 NEWTONS

Description : A 10 kilogram body initially moving with a velocity of 10 meters per second makes a head-on collision with a 15 kilogram body initially at rest. The two objects stick together. What is the velocity of the combined system just after the collision?

Last Answer : ANSWER: 4 METERS PER SECOND 

Description : An automobile is travelling at 25 m/s. It takes 0.3 second to apply the brakes after which the deceleration is 6 m/s2. How far, in meters, does the automobile travel before it stops? a.45 b.107 dynes c.40 d.50 e.60

Last Answer : e. 60

Description : How much time is needed for a force of 20 Newtons to change the velocity of a 5 kilogram mass by 4 meters per second?  

Last Answer : ANSWER: 1 SECOND

Description : Carlos is pulling a 40 kilogram cart with a horizontal force of 100 newtons. The force of friction on the cart is 20 newtons. The acceleration of the cart is: w) 2 meters per second squared x) 2.5 meters per second squared y) 20 meters per second squared z) 200 meters per second squared

Last Answer : ANSWER: W -- 2 METERS PER SECOND SQUARED

Description : A 2 kilogram mass accelerates at 5 meters per second squared for 3 seconds. What impulse has acted on the mass? 

Last Answer : ANSWER: 30 NEWTON-SECONDS or 30 KILOGRAM-METERS PER SECOND 

Description : A girl throws a 0.1 kilogram ball at a wall. The ball hits the wall perpendicularly with a velocity of 5 meters per second and then bounces straight back with a velocity of 4 meters per second. The ... .4 kilogram-meters per second y) 0.5 kilogram-meters per second z) 0.9 kilogram-meters per second

Last Answer : ANSWER: Z -- 0.9 KILOGRAM-METERS PER SECOND 

Description : What kind of energy does a bicyclist have when riding down hill?

Last Answer : Feel Free to Answer

Description : When a 2 kilogram mass is suspended from a spring, the spring stretches 4 cm. The force constant of the spring is approximately:+ w) .5 newtons per meter x) 5 newtons per meter y) 50 newtons per meter z) 500 newtons per meter

Last Answer : ANSWER: Z -- 500 NEWTONS PER METER

Description : A Newton is equal to which of the following? w) kilogram-meter per second x) meter per second squared y) kilogram-meter per second squared z) kilogram per meter-second

Last Answer : ANSWER: Y -- KILOGRAM-METER PER SECOND SQUARED

Description : What is the hydrostatic pressure at the bottom of a pool 6 meters deep? w) 60,000 Newtons per meter squared x) 6,000 Newtons per meter squared y) 600 Newtons per meter squared z) 60 Newtons per meter squared

Last Answer : ANSWER: W -- 60,000 NEWTONS PER METER SQUARED

Description : A child weighing 50 Newtons is on a swing. He goes from a minimum height of 0.2 meters to a maximum height of 1.5 meters. His maximum speed is closest to: w) 3 meters per second x) 5 meters per second y) 7 meters per second z) 9 meters per second

Last Answer : ANSWER: X -- 5 METERS PER SECOND

Description : A 10 kilogram object falls from a cliff 100 meters high. At the midpoint of its fall its total energy is: w) 2450 Joules x) 4900 Joules y) 10,000 Joules z) 20,000 Joules

Last Answer : ANSWER: Y -- 10,000 JOULES

Description : A spring with a force constant of 100 Newtons per meter is loaded with a mass of 1.0 kilogram. The period of vibration of this system is: w) .03 seconds x) .06 seconds y) .31 seconds z) .63 seconds

Last Answer : ANSWER: Z -- .63 SECONDS 

Description : The speed at which a wave propagates down a string is 300 meters per second. If the frequency of this wave is 150 Hertz, what is the wavelength of this wave?

Last Answer : ANSWER: 2 METERS

Description : The energy dissipated when a car hits a tree at 70 miles per hour is ABOUT how much greater than that dissipated at 50 miles per hour? w) 20 percent x) 40 percent y) 70 percent z) 100 percent

Last Answer : ANSWER: Z -- 100 PERCENT

Description : The speed of sound in air at sea level is approximately------? A. 300 meter per second B. 320 meter per second C. 340 meters per second (Answer) D. 370 meter per second

Last Answer : C. 340 meters per second (Answer)

Description : A noodles merchant buys two varieties of noodles the price of the first being twice that of the second. He sells the mixture at Rs 17.50 per kilogram thereby making a profit of 25% . If the ratio of the amounts of the first noodles ... , Rs 10 B) Rs 24, Rs 12 C) Rs 16, Rs 8 D) Rs 26, Rs 13 E) NONE

Last Answer : Answer: A

Description : A 10 kilogram ball falls from a height of 5 meters and rebounds from the floor to a height of 3 meters. The energy lost by the ball is: w) 20 joules x) 98 joules y) 196 joules z) 294 joules 

Last Answer : ANSWER: Y -- 196 JOULES

Description : A worker lifts a 10 kilogram block a vertical height of 2 meters. The work he does on the block is: w) 5 Joules x) 20 Joules y) 49 Joules z) 200 Joules

Last Answer : ANSWER: Z -- 200 JOULES

Description : The radiator of a room contains 10 kilogram of water. If the water gives off 50,000 calories of heat to the room, the drop in temperature of the water is: w) 1 degree Celsius x) 2 degrees Celsius y) 5 degrees Celsius z) 10 degrees Celsius

Last Answer : ANSWER: Y -- 5 DEGREES CELSIUS

Description : What would you do if you found that your child had removed the brakes from his/her bicycle?

Last Answer : What? Why would a kid do that? I'd ask why they did it and explain to him or her that it's very dangerous and make them put the brakes back. If they seemed to comprehend why it was wrong ... to be some sort of punishment I'm not sure though. It really depends on the kids reaction and explanation.

Description : What is the potential energy of a 10 kilogram cube 500 meters above the ground?

Last Answer : ANSWER: 49,000 JOULES (accept 50,000 joules, uses g = 10m/s2) 

Description : If a sled has a constant acceleration of 2 meters per second squared and starts from rest, the distance in meters that it will have covered after 5 seconds is: w) 10 meters x) 20 meters y) 25 meters z) 50 meters

Last Answer : ANSWER: Y -- 25 METERS

Description : When a slingshot exerts a 10 Newton force on a rock, the rock accelerates at 50 meters per second squared. What force is required to accelerate the rock to 150 meters per second squared? 

Last Answer : ANSWER: 30 NEWTONS 

Description : Have any Jellies tried the Walkydog bicycle attachment that allows your dog to go with you on bike rides?

Last Answer : No, I haven’t tried it. I have been considering skijoring with my malamute, I’m afraid of hitching a bicycle ro him with the way he loves to pull…

Description : If a child runs into the road 45 to 50 feet ahead of your car what is the highest speed from which you can stop with good brakes?

Last Answer : About 20 mph, but it would depend greatly on other factors suchas road conditions, size and weight of vehicle, operator reactionspeed, etc.

Description : What is the wavelength in millimeters of a sound wave whose frequency is 35 KILOHERTZ. Assume the speed of sound is 350 METERS PER SECOND? w) 100 millimeters x) 1,000 millimeters y) 10 millimeters z) 1/10 millimeters

Last Answer : ANSWER: Y -- 10 MILLIMETERS 

Description : A girl throws a 2 kilogram rock vertically upward. It reaches a maximum height of 5 meters. What is the kinetic energy of the rock the instant it leaves the girl's hand?

Last Answer : ANSWER: 100 JOULES (accept 98 joules)

Description : A 40 kilogram girl climbs a vertical distance of 5 meters in twenty seconds at a constant velocity. How much work has the girl done?

Last Answer : ANSWER: 2000 JOULES or 1960 JOULES

Description : A blender has a power of 0.3 kW. It is used to make a fruit smoothie, which takes 50 seconds. How much energy is used Give your answer in kilojoules.kJ?

Last Answer : 15 KJ

Description : The potential difference across a 4 ohm resistor is 20 volts. Assuming that all of the energy dissipated by this resistor is in the form of heat, how many joules of heat are radiated in 10 seconds?  

Last Answer : ANSWER: 1000 JOULES

Description : Suppose a crane lifts a 900 kilogram wrecking ball 12 meters above a concrete slab. 105,840 Joules of potential energy are stored in the wrecking ball. Now the ball is dropped. When the ball is 6 meters above the concrete slab, what is it's potential energy in Joules? 

Last Answer : ANSWER: 52,920 JOULES

Description : How many kilojoules of heat are generated when two basic methane are taught ?

Last Answer : When two basic methane are taught, 180 kilojoules of heat is generated.

Description : The average weight of 45 passenger on board an aircraft is 50 kg. If the weight of 5 members of the crew is added, the average is reduced by half kilogram . What is the average weight of the crew members?

Last Answer : Total weight of 45 passenger = 45 x 50 = 2250 kg Total weight of 45 passenger and 5 crews = 50 x 49.5 = 2475 kg Total weight of 5 crews = 2475-2250 = 225kg Average weight of 5 crews = 225/5 = 45kg.

Description : The speed of sound (at sea level) in air is: w) 340 meters per second x) 400 meters per second y) 500 meters per second z) 760 kilometers per second

Last Answer : ANSWER: W -- 340 METERS PER SECOND

Description : A helicopter is ascending vertically with a constant speed of 6 meters per second relative to the ground. At the instant the helicopter is 60 meters above the ground it releases a package. What is ... of the package, relative to the ground, the instant the package is released by the helicopter?

Last Answer : ANSWER: 6 METERS/SECOND UP

Description : A toy train moves in a circle of 8 meters radius with a speed of 4 meters per second. What is the magnitude of the acceleration of the train?

Last Answer : ANSWER: 2 METERS PER SECOND SQUARED