Physics OAT

A young boy pulls his red wagon down the street by exerting a force on the handle of 2 Newtons at an angle of 30 degrees to the horizontal. What is the acceleration of the wagon in m/s^2 if it has a mass of 10 kg? - answer-.2 cos 30 degrees F = ma or a = F/m An object with a density of 2.2 g/cm^3 is dropped into a container filled with a liquid of density 2.1 g/cm^3. Which of the following best describes the state of the object? - answer-The object sinks to the bottom of the container A ball is thrown vertically upward. Which of the following best describes both the velocity and acceleration of the ball at its highest point? - answer-The velocity is zero and acceleration is 10 m/s^2 One liter of a monatomic gas is held at a temperature of 200K. Which of the following statements best describes the speed of the atoms of the gas? - answer-The atoms have a distribution of speeds with a typical speed proportional to the square root of the temperature - V = square root 3RT/M A large metal storage tank is completely filled with crude oil. Which of the following best describes the outward pressure on the wall of the container at a depth of one half of the height of the tank? - answer-The outward pressure equals the fluid pressure at that depth. The strong force between two adjacent protons in the nucleus is - answer-attractive Two children, Tim and Jill, sit on a seesaw of length 4 meters. Tim weighs 400 Newtons and sits at a position of 1 meter to the left of the fulcrum. When Jill sits at a position of 2 meters to the right of the fulcrum, the seesaw is balanced. What is Jill's weight in Newtons? - answer-200 N Torque equation An object experiences an acceleration of 5 m/s^2 when under the influence of a 20-Newton force. What is the mass of the object? - answer-4 kg F = ma A real object is placed in front of a spherical convex mirror. The image produced by the mirror is - answer-always virtual and upright - mirror equation The human eye contains a thing converging lens whose focal length is adjusted by the ciliary muscles to produce a focused image on the retina which is at a fixed distance from the lens. With age, the minimum focal length attainable increases. What effect can this have on an aging persons vision. - answer-This person can have difficulty clearly seeing close objects A sound wave has a frequency of 680 Hertz. If the distance between adjacent wave crests is .5 meters, then what is the wave speed in m/s? - answer-340 v = f x wavelength A person riding at a steady pace on an exercise bicycle generates 40 Watts of power. How long does it take the person to burn off 24,000 Joules of energy. - answer-10 minutes Power = energy/time A negatively charged plastic rod is brought near an uncharged ball which is made from an insulating material. Which of the following best describes the effect of the rod on the ball? - answer-The ball is attracted to the rod Which of the following best describes how a rocket lifts off of a launching pad? - answer-The downward momentum of the exhaust gases results in the upward momentum of the rocket