A man of mass 60 kg runs up a flight of 30 steps in 40 s. If each step is 20 cm high, calculate his power. Take g 10 m/s.

Q: How much power is developed by an airplane that cruises at 300 m/s when the thrust of its engine is…

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Q: A cat knocks a 11.93 kg toy mouse across the floor with 15.87 N of force. If the cat did 17.9 J of…

A: Answer Given data  Weight of the toy mouse = 11.93 kg Force F = 15.87 N  Work done W = 17.9 J The…

Q: A light aircraft that weighs 1600 N is accelerated at 8m/s/s for 15 seconds. The work done on the…

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Q: It takes a force of 35 N to stretch a 45-cm spring to 90 cm and hold it there. How much work was…

A: Given The force to stretch the spring is F=35 N. The initial length of spring is xi=45 cm. The…

Q: what is the kinatic energy of a system with a speed of 4.30m/s and a mass of 410 kg after a distance…

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Q: A forklift applies 2020 N of force to lift items a distance of 2.5 m in 2.8 s. What is the power…

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Q: A cyclist in a race must climb a 5° hill at a speed of 8 m/s. If the mass of the bike and the biker…

A: Given: The angle of inclination of the hill = 50 Speed of the cyclist = 8 m/s Mass of the bike and…

Q: What would be the power output (in-hp) of a 1750kg car if it can acend to the top of a 285m high…

A: The expression of work- energy theorem,

Q: A man with 80.0 kg mass climbs a stairs with a height of 7.0 m within 15.0 seconds. What is his…

A: P=Et=mght

Q: An engine develops 10 kW of power. How much time will it take to lift a mass of 250 kg to a height…

A:

Q: What is the total mechanical energy of falling baseball from the highest of 4m, 3.22m and 2.25m? For…

A: Here we have to apply conservation of mechanical energy Conservation of mechanical energy According…

Q: A ball of 7 kg has velocity given by ü = ( 6 î - 5 ĵ + 2 k ) m/s What is the kinetic energy? Answer…

A: Mass of the ball is m = 7 kg velocity of the ball is v = 6i - 5j +2k

Q: If 5 J of work are needed to stretch a spring 10cm beyond equilibrium, how much work is required to…

A: Given Data Work required to stretch the string is W1=5 J The spring is stretched by a length x1=10…

Q: A 70 kg person runs up a staircase 3.0 m high in 3.5 s.  How much horsepower does he develop in…

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Q: If a 75 kg runner can accelerate from standing start to a speed of 10 m/s in 3 seconds, how much…

A: Since the runner starts from a standing position, the initial velocity of the runner is u=0 m/s.…

Q: Mohan, having a mass of 40 kg, runs up a staircase of 50 steps in 10 s. If the height of each step…

A: Mass (m) = 40 kg Height of 1 step = 15 cm = 0.15 m Height of 50 steps (h) = 50 * 0.15  = 7.5 m Time…

Q: How much work is needed for a 75-kg runner to accelerate from 3.2 m/s to 5.2 m/s?

A: Given:             Mass of runner M=75kg           Accelerates from 3.2 m/s

Q: Find the power output of a 2-m dash-runner who accelerates from 0 to 4 m/s in 0.5 s if he is 60 kg.

A: Given Mass of runner m=60kg Initial velocity u=0m/s Final velocity v=4m/s Time t=0.5s

Q: Calculate the power output in watts and horsepower of a shot-putter who takes 1.20 s to accelerate…

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Q: If the ball is dropped with an initial potential energy of 19800J what would be its maximun kinetic…

A: Solution: According to the conservation of energy, total energy of the ball is constant. Hence,…

Q: a box of mass 3.5 kg being accelerated along the floor at 3.9 m/s2. If this block is being…

A: Given data- Mass of box =3.5 kg Acceleration a=3.9 m/s2 Initial velocity Vi=0 m/s (rest) Time period…

Q: An object with mass 99 kg is moving at the velocity of −3.6 m/s. What is its kinetic energy in the…

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Q: Calculate the total kinetic energy, in Btu, of an object with a mass of 10 lbm when its velocity is…

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Q: How much work is done by a person lifting a 4.1 kg object from the bottom of a well at a contact…

A: Given Data: The mass of an object is, m=4.1 kg The contact speed is, v=2.2 m/s The time required for…

Q: If a 600 N student climbed a 15 ft flight of stairs in 8 sec, what horsepower did that student…

A: Given data: Weight (mg) = 600 N High (h) = 15 ft Time (t) = 8 s Required: The power (P) in…

Q: An engine develops 15 kw of power. How much time does it take to lift 250 kg to a height of 30m ?

A:

Q: If it takes 10.0 J of work to move an object 2.0 meters, what is the weight of the object?

A: The work done to move an object to a distance d is given as,…

Q: How much work is needed for a 73-kg runner to accelerate fromrest to 7.7 m>s?

A:

Q: When doing a chin-up, a physics student lifts her 420N body a distance of 0.25 meters in 2 seconds.…

A: Recall, Power=W/t And Work done=mgh

Q: Abox is moved using 200 N of force over a distance of 15 m. If the box is moved in 1.4 seconds, how…

A: Power is equal to the rate of work done with respect to time.So if W amount of work is done within…

Q: If 3.0 J of work is done in raising a 225 g apple, how far is it lifted?

A: Given W =3.0J mass = 225g so, F = 0.225 kg x 9.8 m/s2 = 2.205N

Q: A force of 35n is needed to keep a 5kg body moving at a constant speed of 7.5m/s. What power is…

A: Write the formula for the power in terms of force and velocity.

Q: Calculate the kinetic energy of a 2 Kilogram cannon ball travelling at: (a) 50 m/s, (b) 45 m/s, (c)…

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Q: A 40-kg mass is lifted through a distance of 20 m in a time of 3 s. What average power is employed?

A:

Q: By definition, when is mechanical work done?

A: Definition:- Mechanical work done is termed as how much energy or force we applied to move an…

Q: A spring has a natural length of 10 cm. If 10 dynes of force are required to hold, it stretched ½…

A: Solution:We know that the force exerted on a spring is given as:F = -kx      -1Where, F is the…

Q: Grace ran 18.084 km in 1.000 h, a world record time. If her kinetic energy was 694 J, what was her…

A: Given Data : The distance traveled by Grace is given as d = 18.084 Km = 18084 m. The time taken by…

Q: What is the work done pushing a box 3 m with a constant force of 100 N? What if the box moves 6 m?

A: The expression for find work done is W=F·d                           ...... (1) Substitute values in…

Q: What is the power demonstrated by a weightlifter when lifting a 420 kg barbell 1.4 meters in 0.65…

A:

Q: What has more kinetic energy: a 500g cream pie flying at 15m/s or a 5kg bowling ball traveling at…

A: Given information:

Q: If the work required to stretch a spring 1 ft beyond its natural length is 12 ft-lb, how much work…

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Q: Lifting 30-kg boxes on a vertical distance of 0.90 m from the ground unto the truck is Ervin's work.…

A:

Q: What is the kinetic energy of a 65.0 kg sprinter running at 2.30 m/s?

A: Given, m = 65kg v = 2.3 m/s

Q: • A farmhand pushes a 26-kg bale of hay 3.9 m across the floor of abarn. If she exerts a horizontal…

A: Expression of work done -  W=F×sWhere,F = Force s = Distance

Q: ) How much work is done when a 50N a Floor pushed along distance 10 m?

A: Given data :- Force F = 50 N displacement d = 10 m

Q: If a person pushes a 2kg box with a force of 10N and a velocity of 10 m/s, what is the power?

A: Answer              100W

Special Relativity

The theory of special relativity discusses how space and time are related to objects traveling along a straight line at a constant speed. Simply stated, as an object reaches the speed of light, its mass becomes infinite and it is unable to move faster than light. This interstellar speed limit has been the topic of much debate in astronomy, and also in science fiction when people consider how to fly over large distances.