SCIN 111 – Space – Flashcards
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When a 10-N object is suspended at rest by two vertical strands of rope, the tension in each rope is
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5N.
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You're lying on the sand on a breezy day when a pesky fly wishes to join you. The breeze is blowing at a steady 2 m/s. In order for the fly to land on you it should hover over you while flying
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Against the breeze at 2 m/s.
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When a falling object gains 10 m/s each second, its acceleration is
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10 m/s^2.
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In a dream you're in a car traveling at 50 km/h and you bump into another car traveling toward you at 48 km/h. The speed of impact is
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98 km/h.
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The gain in speed each second for a freely falling object is about
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10 m/s.
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Fido weighs 120N and carries Trixie who weighs 40N on her back. The support force on Fido's feet is
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160N.
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You toss a ball upward where air resistance is negligible. After the ball leaves your hand the force on it
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Is the single force due to gravity, always directed downward.
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A skydiver who weighs 500N reaches terminal velocity at 90 km/h. The air resistance on the skydiver is
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500N.
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A hockey puck slides across a frozen pond. If ice friction and air resistance are neglected, the force needed to keep the puck sliding at constant velocity is
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0N.
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Inside the interior of a truck that moves at constant velocity is a package that drops from the midpoint of the ceiling. The package hits the floor
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Ahead of the midpoint of the ceiling.
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An object that has kinetic energy must be
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Moving.
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The distinction between impulse and force involves the
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Time the forces acts.
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Compared with falling on a wooden floor, a wine glass may not break when it falls on a carpeted floor because of
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Longer time to stop.
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A lunar month is about 28 days. If the Moon were farther from Earth than it is now, the lunar month would be
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More than 28 days.
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An Earth satellite is in an elliptical orbit. The satellite travels fastest when it is
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Nearest the Earth.
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The Earlybird communication satellite hovers over the same point on Earth's equator indefinitely becuase
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It's orbital period is 24 hours.
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Compared with the mass of a certain object on Earth, the mass of the same object on the Moon is
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The same.
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A 3000N bear grasping a vertical tree slides down at a constant velocity, The friction force between the tree and the bear is
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3000N.
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When an object falls through the air, as velocity increases it's acceleration
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Decreases.
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Two identical freight cars roll without friction towards each other on a level track. One car rolls at 2 m/s and the other car rolls at 1 m/s. After the cars collide, they couple and roll together with a speed of
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0.5 m/s.
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A projectile is launched at an angle of 15 degrees above the horizontal and lands downrange, With no air resistance, what other projection angle for the same speed would produce the same downrange distance?
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75 degrees.
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Aristotle believed that natural laws could be understood by
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Logic.
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A 10N block and a 1N block lie on a horizontal frictionless table. To push them with equal acceleration, we would have to push with
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10 times as much force on the heavier block.
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Two billiard balls having the same mass roll toward each other at the same speed. What is the net momentum of the two-ball system?
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0 kg x m/s.
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A "weightless" astronaut in an orbiting space vehicle is
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Without a support force.
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The equilibrium rule F=0 applies to
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Objects or systems in uniform motion in a straight line.
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An object travels at 8M in the 1st second of travel, 8M again during the 2nd second of travel and 8M again during the 3rd second. Its acceleration is
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0 M/S^2.
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If a jaguar sports car accelerates from zero to 100km/h in 3.0 seconds its acceleration is
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33.3 KM/H/S.
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The two measurements necessary for calculating average speed are
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Distance and time.
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A 50N object falling in air experience 50N of air resistance. The amount of net force on the falling object is
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0N.
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When sign painters Burl and Paul stand on opposite ends of a scaffold, the tensions in each of the two supporting ropes
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Depend on the weight of each Burl and Paul.
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During each second of free fall, the speed of an object
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Increases by the same amount.
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1KG mass at Earths surface weighs about
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10 N.
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If you toss a ball straight upward at 40m/s with no air resistance, 6 seconds later its speed is
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20 m/s.
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A 10N falling object encounters 4N of air resistance. The net force on it is
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6N.
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A sheet of paper can be pulled from beneath a box of cereal without toppling it if the paper is jerked quickly. This best demonstrates that
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The box has inertia.
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You toss a ball upward where air resistance is negligible. After the ball leaves your hand the force on it
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Is the single force due to gravity. Always directed downward.
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A light woman and a heavy man jump from an airplane at the same time and open their same size parachutes at the same time. Which person will get to a state of zero acceleration first?
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The light woman.
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A ball thrown straight up takes 10 seconds to go up and return to the ground. Because of air resistance the time taken for the ball just to go up is
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Less than 5s.
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If you drop an object, it will accelerate downward at a rate of 10 m/s^2. If you instead throw it downward, its acceleration in the absence of air resistance will be
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9.8 m/s.
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Freddy Frog drops vertically from a tree onto a horizontally moving skateboard, Freddy's speed
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Decreases.
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Lifting a 100N Load with 50N of force lifts it
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50N.
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Consider driving into a massive concrete wall with no "give", versus having a head on collision at the same speed with an identical car moving toward you at the same speed. It would be more damaging to hit the
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Both the same.
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A heavy truck and a small car rolling down a hill at the same speed are forced to stop in the same amount of time. Compared with the force to stop the car, the force needed to stop the truck is
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Greater.
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A driver who weighs 500N steps off a diving board 10M above the water hits the water with kinetic energy of
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5000J.
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Inside a freely falling elevator you would experience no
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weight (weightlessness)
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The planet Jupiter is about 300 times as massive as Earth, yet on its surface you would weigh only about 3 times as much. This is because
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Large radius.
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The force of gravity acts on all apples on an apple tree. Some apples are twice as far from the ground. Such twice as high apples of the same mass, have
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Practically the same weight.
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Two motorcycle stunt drivers, one light and the other much heavier, drive their motorcycles up and off and inclined ramp at identical speeds. They both rise in the air and land downrange. Neglecting air drag, the one to attain the greatest height and the greatest range is the
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Both the same.
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Galileo said that if you rolled a ball along a level surface it would
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Keep rolling without slowing down in no friction acted upon it.
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What is the acceleration of a car that maintains a constant velocity of 100KM/H for 10s?
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0.
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An object is pulled with two forces, 10N northward and 15N southward. The magnitude of the net force is
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5N.
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When you toss a coin straight up, it moves upward, turns around, and drops. During this time the acceleration of the coin is
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Downwards and constant.
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A karate chop breaks a board with a blow of 3000N. The force that acts on the hand during this event is
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3000N.
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An object in motion will continue in motion with
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All Inpulse, momentum and acceleration.
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An open freight car rolls friction free along a horizontal track in vertically pouring rain. As water accumulates in the car, its speed
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Decreases.
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When the distance between two stars doubles, the force between them
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Decreases by one half.
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What did Galileo incorporate in his study of motion that Airistotle overlooked?
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The role of time.
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While a car travels around a circular track at a constant speed, its
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No written answer.
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A piece of taffy slams into and sticks into another identical piece of taffy that is at rest. The momentum of the two pieces of taffy stuck together after the collision is the same as it was before the collision. Kinetic energy is a different story, for part of it turns into heat. What percentage of the kinetic energy converts into heat?
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50%.
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A very massive object A and less massive object B move toward each other under the influence of gravity. Which force, if either, are greater?
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Both are the same.
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A girl pushes a cart to the left with a 100N force. A boy pushes it to the right with 50N of force. The net force exerted on the cart is
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50N to the left.
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A force of 1N accelerates at a 1KG mass at 1M/S^2 The acceleration of a 2KG mass acted upon by a force of 2N is
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The same.
