14. If the photon is travelling towards earth, from a region with lower gravitation, the shift will be towards a _______ in the wavelength.

a. Increase

b. Decrease

c. No change

d. None of the above

15. Gravitational waves carry energy and momentum, travel at a speed

a. Slower than that of light

b. Faster than that of light

c. Same speed of light

d. None of the above

16. Gama rays can be considered as _____

a. Wave

b. Particles

c. Both particles and waves

d. None of the above

17. By considering the electromagnetic radiations are particles, we can explain the following properties

a. Reflection

b. Refraction

c. Interference

d. Diffraction

18. In Young’s double slit experiments, the central fringe is always

a. Bright

b. Dark

c. Bright or dark depends on the length between screen and slits

d. Bright or dark depends on the length between slits

19. According to Stefan’s law total radiant heat energy emitted from a source is proportional to

a. T4

b. 1/T4

c. T2

d. 1/T2

A spring stretches 4.0cm when a load of 20N suspended. How much will the spring stretch if 50.0N load is suspended from it and it does not reach it's elastic limit?

2. You purchase a 500g sample of gold and want to know if it is pure to see if you were cheated. You found the sample when lowered into water displaced 27.5 ml. Was the sample pure gold?

A toy car starts from rest and accelerates on a straight road at a rate of 3m/s^2 for 5 seconds. In the next 2 seconds, it continues to move at a constant speed. Finally, it accelerates at a rate of 2m/s^2 until it stops in the rest of the rest of the time. Find its

a.) Displacement

b.) Speed at t=6 seconds

c.) plot the following graphs:

I. x vs. t

II. v vs. t

III. a vs. t

How would astronomers use spectra A, B and C to precisely calculate how fast the star was moving? How would the speed the star is moving allow astronomers to be able to deduce information about the orbiting planet? What type of information could the astronomers calculate?

A ray of light impinges from air onto a block of ice (n = 1.309) at a 33.0

A small metal sphere has a mass of 0.15 g and a charge of -21.0 nC. It is 10.0 cm directly above an identical sphere that has the same charge. This lower sphere is fixed and cannot move. If the upper sphere is released, it will begin to fall.

What is the magnitude of its initial acceleration?

An electron is accelerated through 2400 V from rest and then enters a region where there is a uniform 1.70-T magnetic field. What are (a) the maximum and (b) the minimum magnitudes of the magnetic force acting on this electron.

You have two blocks, with respective masses of 8 kg and 12 kg sitting next to each other on a table. You decide to move them both together, and push on the 8 kg block with a net force of 120 N such that it pushes the 12 kg block along with it.

a. Find the acceleration for both blocks.

b. Will both blocks feel the same net force? Explain.

c. Draw a force diagram on the 8 kg block, and find a force equation for the horizontal forces acting on it.

d. Draw another force diagram on the 12 kg block, and find a force equation for the horizontal forces acting on it.

e. Explain how Newton's 3rd law applies to your answers in part C and D.

Two friends, Barbara and Neil, are out rollerblading. With respect to the ground, Barbara is skating due south at a speed of 3.5 m/s. Neil is in front of her. With respect to the ground, Neil is skating due west at a speed of 3.0 m/s. Find Neil's velocity ((a) magnitude and (b) direction relative to due west, as seen by Barbara.

A 3.0-cm-diameter, 14-turn coil of wire, located at z = 0 in the xy-plane, carries a current of 7.5 A. A 2.0-mm-diameter conducting loop with 2.0× 10^−4 Ω resistance is also in the xy-plane at the center of the coil. At t = 0 s, the loop begins to move along the z-axis with a constant speed of 75 m/s.

What is the induced current in the conducting loop at t = 200 μs? The diameter of the conducting loop is much smaller than that of the coil, so you can assume that the magnetic field through the loop is everywhere the on-axis field of the coil.

In class we learned about Kate, a bungee jumper with mass ? = 50.0 kg who jumps off a bridge of height ℎ = 25.0 m above a river. After she jumps, the bungee cord – which behaves as an ideal spring with spring constant ? = 28.5 N/m – stretches to a new equilibrium with length ?? = 20.0 m (since this is the new equilibrium, let us refer to it as ? = 0 in Hooke’s law and in the elastic potential energy). Note that I have changed the numbers a bit from the ones in class.
After hanging out at this new equilibrium for a bit, Kate starts to get worried. She yells up to her friend Ken, who is frantically trying to figure out how to hoist her back up. After a couple of hours of this, Kate starts to get hungry. She begs Ken to throw her down a backpack full of provisions with mass ? = 15.0 kg. Ken complies, dropping the bag from the bridge with no initial velocity. Throughout this problem you may neglect all sources of friction or other non-conservative forces.

a) Kate catches the bag when it gets to her. What are the momenta of Kate and the bag just before she catches it? What about after?

b) What is the total energy of Kate plus the bag before and after the collision? Is energy conserved during the process of catching the bag?

c) After Kate catches the bag, the bungee cord starts to stretch. What is her downward speed when she hits the river?

d) Sensing her impending doom, Kate thinks fast and strips off her heavy winter coat, which has a mass of 2.00 kg. Just before she's about to go into the river, she throws the coat downward with all her might. With what speed must she throw the coat to avoid drowning?

A shot-putter throws the shot with an initial speed of 11.2 m/s from a height of 5.00 ft above the ground. What is the range of the shot if the launch angle is (a) 24.0 ∘ , (b) 30.0 ∘ , (c) 42.0 ∘ ?

A spring is attached to an inclined plane as shown in the figure. A block of mass m = 2.75 kg is placed on the incline at a distance d = 0.294 m along the incline from the end of the spring. The block is given a quick shove and moves down the incline with an initial speed v = 0.750 m/s. The incline angle is θ = 20.0°, the spring constant is k = 450 N/m, and we can assume the surface is frictionless. By what distance (in m) is the spring compressed when the block momentarily comes to rest?

Ideal vs real battery

a. An ideal battery doesn't exist, are all batteries real?

b. Is the chemical reaction the reason why there is internal resistance?

c. When learning ohms law why to use examples of ideal batteries?

We often think about two-dimensional motion in terms of a projectile, like someone throwing a ball up in the air. Consider, instead, the surface of an air-hockey table, where the puck travels horizontally from one end of the table to the other. Imagine you’re standing at one end of the table and answer the following questions in your initial post to the discussion.

1. Describe the shape of the puck’s path, starting from the end of the table where you’re standing, as it undergoes the following types of motion:
   1. acceleration in the x-direction
   2. acceleration in the y-direction
   3. constant velocity in the x-direction with acceleration in the negative y-direction
2. What must be true of x-velocity and y-velocity for the puck to travel at a 45-degree angle?
3. How can you make the angle steeper or shallower?
4. Can the puck follow a straight path if it’s accelerating in one or both directions? Choose your own orientation for the coordinate system.