(III) One car has twice the mass of a second car, but onlyhalf as much kinetic energy. When both cars increase theirspeed by 8.0 m/s they then have the same kinetic energy.What were the original speeds of the two cars?

Q: You give 90 J of kinetic energy to a 1 kg stone when you throw it. By how much do you increase its…

A: The energy gained by the stone = 90 Joules. Mass of the stone (m) = 1 kg.

Q: Calculate the kinetic energy in Joule, of a car of mass 1800kg travelling at 40km/h.

A: Recall KE=1/2mv^2 m=1800kg v=40km/hr=11.11m/s

Q: If an automobile were to have a 100% efficient engine, transferring all of the fuel’s energy to…

A: The efficiency of automobile is 100 %. This means that the efficiency is 1.

Q: Does a larger net force always produce a larger change inkinetic energy than a smaller net force?…

A: By work-energy theorem, change in kinetic energy is equal to the work done.

Q: A ball of mass 0.320 kg is thrown upward, rising 12.1 m above the point at which it was released.…

A:

Q: Does the kinetic energy of a car change more when it goes from 10 to 20 km/h or when it goes from 20…

A: The change in kinetic energy when the car moving from 10 to 20 km/h is ΔKE=12m20 km/h2-10…

Q: A 0.25-hp motor is used to lift a load at the rate of 5.0 cm/s. How great a load can it raise at…

A: Given: The power is 0.25 hp. The constant speed of the motor is 5 cm/s.

Q: A world-class sprinter running a 100 m dash was clocked at 5.4 m/s 1.0 s after starting running and…

A:

Q: A 2-kg crate is moved horizontally by 3 m by a 4-N force with a speed of 1 m/s. If that is, how much…

A: m= 2 kg d = 3m F = 4 N v = 1 m/s

Q: Say I lift a box from the ground straight up to 1m in 2s. If I lift the same box from the ground but…

A:

Q: A ball of mass 0.270 kg is thrown upward, rising 11.1 m above the point at which it was released.…

A: Given:

Q: vicky mass was 101kg, while mary is at 96kg, and they both jumped up exactly 1.0m.  Who had more…

A: In this case, the velocity is directly proportional to the square root of the height. so here height…

Q: In the absence of air resistance, a ball thrown vertically upward with a certain initial KE will…

A: When air resistance is a factor affecting the ball, it will return to its original level with the…

Q: If the speed of a particle is doubled, what happens to its kinetic energy?

A:

Q: If your friend pushes a lawnmower 4 times as far as you do while exerting only half the force, which…

A: The work is force times distance. Your friend uses a half of the force but goes four times as far.…

Q: The first car has twice the mass of a second car, but only half as much kinetic energy. When both…

A: The energy of the object that is because of the motion of the object is known as kinetic energy.…

Q: In the high jump, Fran's kinetic energy is transformed into gravitational potential energy without…

A: Given data: Height (h) = 2.20 m Final speed (vf) = 0.903 m/s Required: Initially minimum speed…

Q: A Boeing 787-9 jetliner has a mass of 245,000 kg in cluding passengers . Its two engines produce a…

A: m = 245000 kg F = 642000 N v = 623km/h = 623*5/18= 173.06 m/s

Q: A ball is initally at rest at the top of a hill and starts to roll down. Where would total energy be…

A: When the ball is at the top Total Energy is in the form of Potential energy

Q: A 2.0-kg mass is released from rest at the top of a plane inclined at 20o above horizontal. If there…

A:

Q: The driver of a passenger car puts the car to "rest" at the speed of 90 km/h, therefore, the car's…

A:

Q: Cite an example wherein  force exerted on a body does no work. Explain.

A: Work done is defined as the product of force, displacement and cosine of angle between force and…

Q: A man of mass 60.0 kg takes 4 seconds to run up a 4-m high stairs. Which of the following gives the…

A:

Q: When a punter kicks a football, is he doing any work on theball while the toe of his foot is in…

A: The punter can only be applying a force when he is in contact with the football. Therefore the…

Q: An apple hanging from a limb has potential energy because of its height. If it falls, what becomes…

A: From conservation of energy, just before hitting the ground, the potential energy will convert into…

Q: - A moving object whose initial KE is 10 J is subject to a frictional force of 2 N that acts in the…

A: Given data:  Initial kinetic energy (KEi) = 10 J Final kinetic energy (KEf) = 0 J Force (F) = 2 N…

Q: Consider a 1200-kg car cruising steadily on a level road at 90 km/h. Now the car starts climbing a…

A: The additional power must be provided by the engine to overcome the component of gravitational force…

Q: a 2.5 kg mass is intially at reston a horizontal surface. an applied force acts in the +x direction…

A:

Q: Calculate the kinetic energy of a 0.15 kg baseball moving at a speed of m 39.0 ". Round your answer…

A:

Q: When a driver applies brakes to keep a car going downhill at constant speed and constant kinetic…

A: In the given case, the car is moving with a constant speed and constant kinetic energy. The…

Q: If the speed of the car is doubled, the kinetic energy of KE = (1/2)mv^2 * Quadrupled O Doubled O…

A: Here given that a car is moving with a speed doubled from its previous .We have to find the final…

Q: When a driver applies the brakes to keep a car going downhill at constant speed and constant kinetic…

A:

Q: a mass of 0.1420 kg and has this speed just before a batter makes contact with it, how much kinetic…

A:

Q: A baseball of mass 0.25 kg is hit at home plate with a speed of 40 m/s. When it lands in a seat in…

A: Given: Mass of the ball = 0.25 Kg Speed of the ball = 40 m/s Horizontal distance from home plate =…

Q: Two stones, one with twice the mass of the other, are thrownstraight up and rise to the same height…

A: Formula for gravitational potential energy is,

Q: Give an example when work done by the force of gravity acting on a body is zero even though body…

A: When a coolie carries a load while moving on a ground, the displacement is in the horizontal…

Q: Using conservation of energy, how fast would a rollercoaster be traveling at a point half way above…

A:

Q: A ball is released from rest on a no-slip surface, as shown. After reaching its lowest point,…

A: To explain: Whether the ball is at a greater height, at a lesser height or at the same height as…

Q: A film of Jesse Owens's famous long jump (Fig. 6–47) in the 1936 Olympics shows that his center of…

A: Given data: Speed at the top of the arc, v=6.5 m/s Height risen by centre of mass, h=1.1 m Let…

Q: If force and distance traveled are tripled, how does that affect work? Is it also tripled or 1/3?:(

A: We know that work depends on force and distance travelled in the direction of force i.e W = F× D…

Q: The engine of the car has a power of 355 hp. If it 800 kg and moves horizontally, what will be its…

A: Power of engine "P"= 355h.p = 264.72kW. mass of car "m"= 800 kg  time taken "t"= 7sec . initial…

Q: For a given person, as the time needed to run up a flight of stairs decreases, the power

A: power=work done  Time taken since the work done to run up a flight of stairs is same and the time…

Q: Calculate the final speed of a 110kg rugby player who is initially running at 8.00 m/s but collides…

A: Given that  mass m is 110 kg. initial speed is 8.00 m/sec  . a backward force of 1.76×104N for…

Q: Does the kinetic energy of a car change more when it goes from 10 to 20km/h or when it goes from…

A: Calculating the change in kinetic energy for the given velocity ranges:

Q: You drop two balls from a tower, one of mass m and the other of mass 2m. Just before they hit the…

A: Given: The mass of the first ball is m. The mass of the second ball is 2m. Introduction: The kinetic…

Q: 6.35 Just before striking the ground, a 2.0-kg mass has 400 J of KE. If friction can be ignored,…

A: