Defy the Odds of Physics Assignments with Us!Physics
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A runner in a marathon passes the 5.00 km mark at 1 oâclock and the 20.0 km mile mark at 3 oâclock. What was the runnerâs average speed during this time?
An astronaut has landed on an unknown planet. She drops a wrench from a height of 2.00 meters above the surface. Â The wrench takes 0.800 seconds to fall to the surface. Â What is the acceleration of gravity on this planet?
An 18-wheel truck pulling a full load of gasoline has a mass of approximately 36,300 kg. If its acceleration as it pulls out of a fueling station is 0.3 m/s2, what is the net force acting on it?
Mars orbits the sun with an average radius of 2.28 x 1011 m. The mass of Mars is 6.42 x 1023 kg. The Sun's mass is 1.99 x 1030 kg. The universal gravitational constant has a value of 6.67 x 10-11 Nm2/kg2. Â What is the value of the gravitational force between the Sun and Mars?
A rubber ball is attached to a string and whirled around in a circle.
a) If the string is 1.50 m long (measured from the center of the ball to the far end of the string) and the ballâs speed is 12.0 m/s, what is the ballâs centripetal acceleration?
b) The mass of the ball is 0.200 kg. What force is acting on this ball as it is whirled in a circle?
A sprinter with a mass of 65.0 kg reaches a speed of 10.0 m/s during a race. Find the sprinterâs momentum at this mass and speed.
A car has a mass of 2,000 kg and is traveling at 28.0 m/s, what is the car's kinetic energy?
A construction crew needs a crane to lift a weight of 5000 N up to the top floor of a building that is 12.0 m above the ground. Â The supervisor needs a crane that can do this in 1.00 minute (60.0 seconds) to do the job in the time allotted to get the construction materials to the top floor. Â How much power should the crane have?
A ball is thrown straight up with an initial speed of 20.0 m/s. How high will the ball be above point where it left the thrower's hand when it stops moving up?
How many calories of heat energy are required to increase the temperature of 50 g of water from 0°C to 100°C. The specific heat capacity for water is 1.00 cal/(g?°C).
A tire pump has a piston with area 0.500 in2. If a person exerts a force of 32.0 lb on the piston while inflating a tire, what pressure does this produce on the air in the pump in psi?
A tanker truck has a capacity of 25,000 lb. of liquid. What volume of antifreeze can it carry? [The weight density of antifreeze is 67.0 lb/ft3.]
The small piston of a hydraulic press has an area of 25.0 cm2. If the applied force is 75.0 N, what must the area of the large piston be to exert a pressing force of 5200 N?
Two iron workers stand 100 m apart. One strikes a steel beam with a hammer. How long does it take for the other to feel the sound through the beam? Assume the velocity of sound in steel is 5200 m/s.
How long will it take a sound wave to travel 500 m in air with a temperature of 30.0 C??
Find the focal length of a mirror that forms an image 2.30 m behind a mirror of an object that is 6.50 m in front of the mirror.
An object with a height of 2.5 cm is placed in front of a concave mirror. Â An inverted image with a height of 3.5 cm is formed 15.5 cm in front of the mirror. Â How far from the mirror was the object placed?
Find the energy of a photon with a frequency of 5.00 x 1016 Hz.
The speed of light in an unknown medium is measured to be 2.76 x 108 m/s. What is the index of refraction of the medium?
The index of refraction in fused quartz is 1.4585. Â What is the speed of light in fused quartz?