Speed KE less. less less, the same the same, less the same, the same greater, the same Answer: Slower because larger mass Less KE because of lower speed which is ². mv…
श्रेणी: Physics
A planet of mass m orbits a start of mass M, where m
The orbital speed equals (2(pi)r)/T The gravitation force equals GMm/r² If the orbital radius r were greater, T …would also be greater. Answer: Orbital speed is d/t d = circumference = 2(pi)r…
Electromagnetic wave
Answer: Requires no material medium and can travel through a vacuum (radio, light, x-ray, etc.)
A person throws a marble straight up into the air, releasing it a short height above the ground and catching it at that same height. If air resistance is negligible, which of the following graphs of position y versus time t is correct for the motion of the marble as it goes up and then comes down?
Up then down (straight) Upside down parabola Pointed curve Weird thing Reflection of a weird thing Answer: Upside down parabola
An object weighing 120N is set on a rigid beam of negligible mass at a distance of 3m from a pivot. A vertical force is to be applied to the other end of the beam a distance of 4m from the pivot to keep the beam at rest and horizontal. What is the magnitiude F of the force required?
10N 30N 90N 120N 160N Answer: 90N Fd – Fd = 0 120×3 – 90d = 0 d=90
Disturbance
Answer: Atoms of the medium are displaced from equilibrium
Wave fronts
Answer: Crests of the wave. Shown in a circular diagram where each is one wavelength apart.
What happens when you jump in the air?
Answer: When you push down on the earth with a force greater than your weight, the earth will push back with the same magnitude force and thus propel you into the air.
Snapshot graph and history graph are…
Answer: Flipped