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Nail tips exert tremendous pressures when they are hit by hammers because they exert a large force over a small area. What force must be exerted on a nail with a circular tip of 1.00 mm diameter to create a pressure of 3.00 X 10^9 N/m^2?  

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A(n) ________________ is positioned as part of a paragraph in a Word document at the location of the insertion point.

A beam has dimensions of b = 18 in., h = 26 in., and d = 23.5 in. and is reinforced with 4 No. 6 bars. The concrete strength is 4,000 psi, and the yield strength of the reinforcement is 60,000 psi. Assuming the reinforcement has yielded, determine the tensile force T in the reinforcement.

Pressure cookers have been around for more than 300 years, although their use has strongly declined in recent years (early models had a nasty habit of exploding). How much force must the latches holding the lid onto a pressure cooker be able to withstand if the circular lid is  25.0 cm in diameter and the gauge pressure inside is 300 atm? Neglect the weight of the lid.

A flea jumps by exerting a force of  1.20 X 10^-5 N straight down on the ground. A breeze blowing on the flea parallel to the ground exerts a force of  0.500 X 10^-6 N on the flea. Find the direction and magnitude of the acceleration of the flea if its mass is 6.00 X 10^-7 kg. Do not neglect the gravitational force.

Conversations with astronauts on the lunar surface were characterized by a kind of echo in which the earthbound person’s voice was so loud in the astronaut’s space helmet that it was picked up by the astronaut’s microphone and transmitted back to Earth. It is reasonable to assume that the echo time equals the time necessary for the radio wave to travel from the Earth to the Moon and back (that is, neglecting any time delays in the electronic equipment). Calculate the distance from Earth to the Moon given that the echo time was 2.56 s and that radio waves travel at the speed of light .

Space debris left from old satellites and their launchers is becoming a hazard to other satellites. Calculate the speed of a satellite in an orbit 900 km above Earth’s surface. (Mass of Earth = 5,979 X 10^24 kg) Consider 900 km as the distance between the satellite and Earth.

Two teams of nine members each engage in a tug of war. Each of the first team’s members has an average mass of 68 kg and exerts an average force of 1350 N horizontally. Each of the second team’s members has an average mass of 73 kg and exerts an average force of 1365 N horizontally. What is the tension in the section of rope between the teams?

Homo sapiens have existed on earth for about 10% of the earth’s history.