Other Physics Answers

A disk rolls smoothly down an incline. (a) If α = 25⁰, calculate the translational acceleration of the center of mass of the disk. (I = 1/2 MR²); (b) Analyze forces acting on the disk. What forces cause the translational motion and the rotational motion of the disk?

neglecting friction and air resistance what force id required to accelerate an automobile weighing 5.0x10n from 60km/hr to 85km/hr in 5minutes

A thin hoop of mass 2 kg and radius 0.2 m can rotate about its central axis. It is initially at rest. (a) The rotational inertia of a rigid body is expressed by I = ∫ r² dm . Use this equation to prove that the rotational inertia of a thin hoop about central axis I = MR² and apply for the thin hoop above. (b) A tangential force F is applied to the rim of the hoop. After 10 s, the angular speed of the hoop is 200 rad/s, find the magnitude of F.

Before collision, block A with mass 1 kg, velocity 5 m/s and block B with mass 2 kg, on a floor are moving towards each other along the x axis. They collide, stick together and move with velocity -2 m/s after collision: (a) Assuming the floor is frictionless, find the velocity of block B before the collision; (b) If the floor is not frictionless, what additional information is required to determine the velocity of block B right before the collision?

A 500g-ball drops vertically onto the ground, hitting with speed 14 m/s. It rebounds to height 5 m. The ball is in contact with the ground for 15 ms. (a) Determine the magnitude of the impulse acting on the ball. Sketch the impulse vector. (b) Calculate the average force acting on the ball. What is the origin of this average force?

Prove that the melting process of a 100-g ice cube initially at -25C in a large room of 35C is irreversible. (c ice = 2220 J/kg.K; L F,ice = 333 kJ/kg; c water = 4190 J/kg.K)

At what temperatures does the RMS speed of O2 molecules equal the escape speed from the Earth and the Moon? (vesc,Earth = 11.2 km/s; vesc,Moon = 2.38 km/s;). Search for the range of temperature of the Moon (daily and night), then explain why the Moon cannot retain the air. 

One mole of O2 gas is taken along an isochoric process from 100 Pa to 200 Pa at volume 1 m3 . Assuming the gas is ideal, find the change in the translational kinetic energy of a molecule. 

An object 1.00cm high is placed 18.0cm from a converging lens forms a real image 2.00cm high. Calculate the focal length of the lens

forces f1 (east) and west f2 are simultaneously applied to 3.0 kg mass. when f2 is east, a= 5.0 m/s east and when f2 is west a=1.0 m/s east. determine the magnitude of f1 and f2