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Questions in physics

[Done] How are work, force, and distance related?

[Done] Two billion people jump up in the air at the same time with an average velocity of 7.0 m/s. If the mass of an average person is 60 kilograms and the mass of Earth is [tex]$5.98 \times 10^{24}$[/tex] kilograms: a. What is the total momentum of the two billion people? b. What is the effect of their action on Earth?

[Done] Calculate the force between one grapefruit and Earth. Earth has a mass of [tex]5.9742 \times 10^{24} \text{ kg}[/tex] and a radius of [tex]6.3710 \times 10^{6} \text{ meters}[/tex]. Assume the grapefruit is resting on Earth’s surface.

[Done] The Lamborghini Diablo sports car can accelerate from 0.0 km/hr to 99.2 km/hr in 4.0 seconds. What is the acceleration of this car? Give your answer in units of kilometers per hour per second.

[Done] Is the following sentence true or false? The faster the particles of a substance are moving, the more energy they have.

[Done] A skier reaches the bottom of a slope with a velocity of 12 meters per second north. If the skier comes to a complete stop in 3 seconds, what is the acceleration?

[Done] A 10 kg bowling ball would require what force to accelerate down an alleyway at a rate of 3 m/s\(^2\)? Given: \[ F = ? \] \[ M = 10 \, \text{kg} \] \[ A = 3 \, \text{m/s}^2 \]

[Done] What is the potential energy of a 3-kilogram ball that is on the ground?

[Done] An engineer in India (standard household voltage = 220 volts) is designing a transformer for use on her upcoming trip to Canada (standard household voltage = 120 volts). If her input coil has 240 turns, how many turns should her output coil have?

[Done] When you whisper, you produce a 10-dB sound. a. When you speak quietly, your voice sounds twice as loud as a whisper. How many decibels is this? b. When you speak normally, your voice sounds 4 times as loud as a whisper. How many decibels is this? c. When you yell, your voice sounds 8 times as loud as a whisper. How many decibels is this?