Suppose you accidentally drop a penny from the observation deck on the 102nd floor of the Empire State Building (the deck is 1245 ft = 380 m above the ground). (a) Ignoring air friction, what will be the penny’s approximate speed when it hits the ground? The approximate speed of the penny when it hits the ground will be ____m/s (b) If the observed speed is actually 65 m/s, what fraction of the system’s change in potential energy was converted to internal energy in the air and/or the penny? About ____ % of the systems change in potential energy was converted into internal energy in the air and/or the penny

Q: A 65-kg skier with an initial speed of 11.2 m/s coasts up a height h=2.6-m high rise as shown in the…

A:

Q: A man on a motorcycle plans to make a jump as shown in the figure. If he leaves the ramp with a…

A: In this case, we can use projectile motion concept because the biker is subjected to no other force…

Q: In the kinetic energy formula, the 1/2 is ignored and you simply multiply the mass by velocity…

A:

Q: A stationary soccer ball of mass m = 0.76 kg is kicked with a constant force of F = 11 N. The…

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Q: A 3 kg ball rolls off a 30 m high cliff, and lands 27 m from the base of the cliff. Express the…

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Q: han on a motorcycle plans to make a jump as shown in the figure. e leaves the ramp with a speed of…

A: u = 32 m/s  ux= 30.4m/s at max height

Q: A 14 kg penguin slides on its belly down an icy, frictionless glacier. If the penguin started from…

A: Write the given values of the problem- Mass=14 kg final speed(vf) vf=14 m/s

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A: In this question it is given that when designing a skyjump ramp for the Olympics  We need to…

Q: 102 kg man is skiing across level ground at a speed of 9.5 m/s when he comes to the small slope 1.4…

A: Given:- The mass of the person m = 102 kg  The speed of the skis at the ground level vg = 9.5 m/s…

Q: Two planets of mass 1 x 1025kg are release from rest 8.0 x 1012 m apart.  What is the speed of the…

A: Given: Mass of planets : m1=m2=m=1×1025 kg Distance r=8.0×1012m To find the speed ''v'' at half the…

Q: Two blocks are connected by a light string that passes over a frictionless pulley as in the figure…

A: (a) According to the conservation of energy,…

Q: You drop a 1.50 kg book to a friend who stands on the ground at distance D= 12.0 m below. Your…

A: Given: D=12.0 m d = 1.80m m = 1.5kg

Q: A 2.31x103 kilogram car starts from rest and coasts down from the top of a 4.15 meter long driveway…

A:

Q: If he leaves the ramp with a speed of 29.5 m/s and has a speed of 27.7 m/s at the top of his…

A: Useful formula: Kinetic energy of an object with mass M & speed v is Ek=12Mv2       ...(1)…

Q: In the sport of skeleton a participant jumps onto a sled (known as a skeleton) and proceeds to slide…

A: Given data The elevation from top to bottom is: h = 126 m   (a) The expression for the potential…

Q: answer the following question "When is the velocity of the mass at a maximum? Justify your answer"…

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Q: If the skier coasts up the hill, what is his speed (in m/s) when he reaches the top plateau? Assume…

A: Energy can neither be created nor destroyed. It is simply converted from one form to another and the…

Q: A child on a sled with a total mass of 45.0 kg slides down an icy hillside with negligible friction.…

A: The vertical height of the hill is about 0.46 m. Here, we use conservation of energy and solve for…

Q: A 2.1 x 103-kg car starts from rest at the top of a 5.5-m-long driveway that is inclined at 15° with…

A:

Q: A 104 kg man is skiing across level ground at a speed of 8.3 m/s when he comes to the small slope…

A: Given that,                     initial velocity(vi)=8.3m/s                     mass of man(m)=104kg…

Q: A small block slides down a frictionless track whose shape is described by y = (x^2) /d for x0. The…

A: given      y=x2d for x<0      y=-x2d for x>0     d=2.33     initial velocity of block =0m/s…

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A: Given in question - Mass of truck(m) = 3500 KgInitial speed(u) = 11 m/sFinal speed(v) = 18 m/sTo…

Q: You drop a 2.20 kg book to a friend who stands on the ground at distance D = 15.0 m below. Your…

A:

Q: A small block slides down a frictionless track whose shape is described by y = (x^2) /d for x0. The…

A: Given values: Equation of y, y=x2d           for x<0y=-x2d       for x>0 Value for d = 2.10 m…

Q: The top of a ski hill sits at an altitude of 2000 m. If you were to "Frenchfry" (go straight down…

A: Here, we have to Use Conservation of energy As difference in altitude is given, we just have to…

Q: 17. A few weeks ago in lab you were releasing gliders down a tilted frictionless air track. Assume…

A: Given Data Angle of the track with the horizontal is θ=18°. The glider passes through the gate after…

Q: A 2.1 ✕ 103-kg car starts from rest at the top of a 5.3-m-long driveway that is inclined at 18° with…

A: The speed of the car at the bottom of the driveway is 11.91 m/s.Explanation:

Q: Two planets of mass 2 x 1025kg are release from rest 9.0 x 1012 m apart. What is the speed of the…

A:

Q: A rock with a mass of 2.80 kg is moving with velocity (6.201 1.40ĵ) m/s. (HINT: v² = v.v.) (a) What…

A: mass of rock = 2.80 kg velocity vector = (6.20i^ - 1.40j^) m/s

Q: fa Saturn V rocket with an Apollo spacecraft attached had a combined mass of 3.2 x 105 kg and eached…

A:

Q: The juggling skateboarder is back outside my office! He starts with a speed of of 3.0 m/s at a…

A: This problem can be solved using the conservation of energy and using kinematic as well. We will…

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A:

Q: A proton (mass m = 1.67 x 10-27 kg) is being accelerated along a straight line at 6.20 × 1011 m/s²…

A:

Q: A 60.0 kg skier with an initial speed of 16.5 m/s coasts up a 2.50 m high rise as shown in the…

A:

Q: You drop a 2.20 kg book to a friend who stands on the ground at distance D = 15.0 m below. Your…

A: Given, mass of the book, m = 2.20 kgdistance, D = 15.0 mfinal distance, d = 1.30 m

Q: Tiny Spring: A tiny silica bead attached to a strand of DNA can be used to study the mechanical…

A: Given, m=7.8×10-15 kgvrms=7.56×10-4 m/s

Static and Kinetic Friction

Kinetic friction comes into existence when there are moving surfaces means in other words we can say that the force which comes into existing between moving surfaces is known as kinetic friction.