Steve Young stands on the 20-yard line, poised to throw long. He throws the ball at initial velocity v0 equal to 15.4 m/s and releases it at an angle θ equal to 45.0∘ .

1) Having faked an end around, Jerry Rice comes racing past Steve at a constant velocity VJ equal to 8.00 m/s, heading straight down the field. Assuming that Jerry catches the ball at the same height above the ground that Steve throws it, how long must Steve wait to throw, after Jerry goes past, so that the ball falls directly into Jerry's hands? (Express your answer to three significant figures.)

2) Jerry is coming straight past Steve at VJ equal to 8.00 m/s. But just as Jerry goes past, Steve starts to run in the same direction as Jerry with VS equal to 1.40 m/s. How long must Steve wait to release the ball so that it falls directly into Jerry's hands? (Express your answer to three significant figures.)

A fugitive tries to hop on a freight train traveling at a constant speed of 5.0 m/s. Just as an empty box car passes him, the fugitive starts from rest and accelerates at a = 4.0 m/s²to his maximum speed of 8 m/s.

(a) How long does it take him to catch up to the empty box car?
_____________ s

(b) What is the distance traveled to reach the box car?
_____________ m

You are standing at x=8.0km and your assistant is standing at x=5.0km. Lightning bolt 1 strikes at x=0km and lightning bolt 2 strikes at x=14.0km. You see the flash from bolt 2 at t=20μs and the flash from bolt 1 at t=51μs.

If not, what was the time difference between the two?

(1)Write a few lines about work, (at least 60 words) examples and units of work and how I recognize work.
(2) Also write a few lines (at least another 50 words) about Kinetic energy (KE) and Potential Energy (PE) and examples. Also write about equations and units of different kind of energy about them.
(3)Try to write a few more lines (of another at least 40 words) about how you can use PE and KE in daily lives.

PLease add sources

A block of mass m₁ = 1.31 kg and a block of mass m₂ = 11.4 kg are connected by a massless string over a pulley in the shape of a solid disk having radius R = 0.250 m and mass M = 2 kg. The fixed, wedge-shaped ramp makes an angle of θ = 30.0° as shown in the figure. The coefficient of kinetic friction is 0.24 for both blocks. Determine the acceleration of the blocks.

One "extreme" example of gravity is a black hole. What would happen to the Earth's orbit if the Sun was suddenly replaced by a black hole of the same mass? Why? (Please ignore any processes that the Earth would experience during the formation of the black hole.) Please break it down for us dummies

A box of mass M sits on the floor of an elevator at rest. Gravity (which has a strength set by the local acceleration due to gravity g) pulls the box and the floor pushes the box. The net or total force on the box is zero.

What is the force on the box from the floor? Give both the magnitude and the direction.

Now imagine that the elevator is accelerating upwards at acceleration a. Now the two forces on the box don’t balance! Because, after all, the box is accelerating upwards. What is the force on the box from the floor in this case?

Now imagine that the elevator is accelerating downwards at accelerationa. Same question.

Now imagine that the elevator is accelerating downwards at accelerationa = g. Same question. Look up the “vomit comet” and tell me what this problem has to do with that airplane.

why would someone be curious about Nuclear Magnetic Resonance (NMR) and Magnetic Resonance Imaging (MRI)? and how is it related to modern physics?   

Starting in Albany, you travel a distance 319 miles in a direction 22.3 degrees north of west. Then, from this new position, you travel another distance 360 miles in a direction 11.0 degrees north of east. In your final position, what is your displacement from Albany?

An unstable nucleus of mass 1.7 ✕ 10−26 kg, initially at rest at the origin of a coordinate system, disintegrates into three particles. One particle, having a mass of m1 = 1.0 ✕ 10−27 kg, moves in the positive y-direction with speed v1 = 5.4 ✕ 106 m/s. Another particle, of mass m2 = 7.0 ✕ 10−27 kg, moves in the positive x-direction with speed v2 = 3.6 ✕ 106 m/s. Find the magnitude and direction of the velocity of the third particle. (Assume that the +x-axis is to the right and the +y-axis is up along the page.)

Suppose that an electron and a proton are placed at a distance of 1.2nm away from each other (about 10 times the radius of a hydrogen atom).

(a) How much is the Coulomb force between the electron and the proton?

(b) Under this Coulomb force alone, how much is the acceleration of the electron towards the proton (in m/s2 )? (Google for the missing information.)

(c) If the electron is instead placed on the edge of the supermassive black hole Sagittarius A* (about 22 million km away from the center), how much is the gravitational acceleration of electron towards the black hole (in m/s2 )? (Google for the missing information about Sagittarius A*.)

(d) For this electron, how does the gravitational influence of the black hole compare to the electric influence of the proton?

A billiard ball rolling across a table at 1.45 m/s makes a head-on elastic collision with an identical ball. Find the speed of each ball after the collision when each of the following occurs.

(a) The second ball is initially at rest.

(b) The second ball is moving toward the first at a speed of 1.10 m/s.

(c) The second ball is moving away from the first at a speed of 0.90 m/s.

Consider the steady, incompressible blood flow through the following vascular network: 100 µm diameter which is 80 mm in length to the first branching point, which can be estimated as a standard tee (flow through run), the branch off the tee turns 45 degrees and undergoes a constriction to 65 µm diameter and the flow through run continues for another 80 mm. The velocity of the blood into the 100 µm diameter vessel is 100 mm/s and 20% of the mass flow rate exits via the branch.

a) What are the velocities of both the run and branch?

b) What is the change in pressure from the inlet to the end of the run?

c) What length would the branch need to be to achieve the same pressure drop?

d) What assumptions did you make in completing this problem.

Two objects of masses m and 8m are moving toward each other along the x-axis with the same initial speed
v0 = 525 m/s.
The object with mass m is traveling to the left, and the object with mass 8m is traveling to the right. They undergo an elastic glancing collision such that m is moving downward after the collision at a right angle from its initial direction.

What is the final speeds of the two objects m and 8m?

What is the angle theta at which the object with mass 8m is scattered? ( counterclockwise from the x-axis)

Three children are riding on the edge of a merry‑go‑round that has a mass of 105 kg and a radius of 1.60 m . The merry‑go‑round is spinning at 22.0 rpm. The children have masses of 22.0, 28.0, and 33.0 kg. If the 28.0 kg child moves to the center of the merry‑go‑round, what is the new angular velocity in revolutions per minute? Ignore friction, and assume that the merry‑go‑round can be treated as a solid disk and the children as point masses.

final angular velocity: ________ rpm