There are 2 charges (3 μC and 4 μC) located at (-4 cm, 0) and (4 cm, 0), respectively.
a. Determine the magnitude and direction of the electric field at (8 cm, 0).b. Determine the magnitude and direction of the electric field at (0, 8 cm).(hint: this problem will require adding vectors. Recall your trig.)(note: for this problem you will need to draw two diagrams on graph paper, which can be downloaded if you don’t have any.)
A beam is attached to a wall by a hinge composed of a single pin. It is supported by a cable attached from the ceiling to the beam 18 m from the pinned end of the beam. The beam is 24 m long and has a mass of 280 kg. Also, there is a 118 kg box of cell phones resting on the beam 5.0 m from the hinge end of the beam. Determine the tension in the cable and the forces acting on the hinge pin.
A hollow sphere (m = 75 kg, R = 1.5 m) is rolling along a level surface at 25 m/s when it encounters a hill angled 30 degrees above the horizontal. Determine the maximum height the hollow sphere achieves before coming to rest on the side of the hill and before subsequently rolling back down again. (Note: the hollow sphere rolls up the hill without slipping.)
A 75 kg crate is pushed down a ramp as shown. The slope of the ramp is 30o above the horizontal as measured from the bottom of the ramp and the μk between the crate and the ramp is 0.20. Determine the acceleration of the crate down the ramp if a 35 N force is applied.
While mountain biking through the woods you encounter a ravine which you need to jump. The ravine is 8 m wide and the side you ride off of is 5 m higher than the side you are to land on. Determine the minimum speed you need to jump the ravine and your time of flight (i.e. the time from when you leave the top of the ravine until you land) if you launch yourself horizontally off the high side of the ravine.
A well on the side of the road (the kind with a bucket attached to a rope and water at the bottom) has a depth of 1.23 m (measured from the upper rim to the surface of the water). The temperature is 20°C, and you just happen to have a set of tuning forks with you. Determine the lowest frequency tuning fork that will create first harmonic resonance (or first position resonance) in the air column in the well. Is this frequency audible to humans? This problem requires a detailed diagram of the well shaft and the standing wave for maximum credit.
In a large soccer stadium, suppose you are sitting 200 m away from the ball as it is kicked.
a. Find the time that elapses before the sound (v = 340 m/s) ofthe ball being kicked arrives at your ear.b. You see the kick much earlier than you hear it. Find the time it takes for light to travel to you (see Appendix C for the speed of light).c. Compare the two times and comment on your result.
A spring that is 5.5 m long is set into vibration so that a 2.5 wavelength wave (a.k.a. a five-loop standing wave) is established with a frequency of 4.4 Hz.
a. Construct and label a detailed diagram of the standing wave.b. Rather than generating a standing wave, suppose a single pulse was sent from one end of the spring to the other end of the spring. Determine the amount of time required for the pulse propagate the length of the spring?
For a new TV series “Stupidity Factor,” contestants are dropped into the ocean (r
= 1030 kg/m3) along with a Styrofoam (r = 300 kg/m3) block that is 2 m x 3 m x 20 cm thick. If too many contestants climb aboard the block and it sinks below the water surface, they are declared “stupid” and abandoned at sea. Find the maximum number of 70 kg contestants that the block can hold. (No fractional contestants, please. They hate it when that happens.)2 AnswersPhysics6 months ago
Wind blows over the top of a 3 m by 20 m flat-roofed house at 30 m/s.
a. If the air pressure inside is normal atmospheric pressure, find the net force on the roof. Assume the roof’s weight is 1500 N.b. If the roof is held on by nails, each of which would require 200 N of force to pull, how many nails would be required to keep the roof in place? (Use rair = 1.29 kg/m3.)
A simple piping system consisting of a small pipe (diameter 6 cm) connected to a larger pipe
(diameter 30 cm) is used to transfer and magnify force from one end to the other. The system is full of water and completely enclosed by two pistons, one on each end. If a force 11.2 N is exerted (additional to the forces already present) on the small piston, then how much additional force is exerted at the larger piston?