1. A 7.00 kg sled is initially at rest on a frictionless horizontal road. The sled is pulled a distance of 2.40 m by a force of 18.0 N applied to the sled at an angle of 24° to the horizontal. Find the change in the kinetic energy of the sled.

2. A 0.24-kg stone is thrown vertically upward with an initial velocity of 7.10m/s from a height 1.30 m above the ground. What is the potential energy of the stone at its maximum height relative to the ground?

Describe the process of combustion. How do flammable materials ignite?

Describe the three methods by which heat moves from one object or area to another.

Explain why it is important for an arson investigator to understand these concepts.

Think about the length of the record groove for every minute of music. Debate whether the record quality depends on the speed the record turns. Given the same size record, does a 33.33 rpm record have higher/lower/the same audio quality as a 45 rpm record?

Does a song on the outside of a 12 inch diameter record have the same/higher/lower audio quality as a song that plays closer to the center of the record?

After 500 years of drifting in space and a brief visit on board the flagship Draconia, Buck Rogers headed to the Federal Directorate of Earth in his spacecraft. His descent consisted of the following stages. Assume that each stage followed immediately after the preceding stage and that the acceleration during each stage was constant. Stage A: Friction with the atmosphere reduced the speed from 19,500 km/h to 1700 km/h in 4.0 min. Stage B: A parachute then opened to slow it down to 340 km/h in 100 s. Stage C: Retro rockets then fired to reduce its speed to zero over a distance of 75 m. (a) Calculate the spacecraft’s acceleration (m/s2 ) during each stage. (b) What total distance (km) did the spacecraft travel in each stage

What is the minimum pushing force required to move the block?

The block is moving and is still being pushed with the force found in part A. What is the magnitude of the friction force?

The block is moving and is still being pushed with the force found in part A. What is the magnitude of the acceleration of the block?

A vernier caliper consists of two scales, Main scale and a vernier scale. the vernier scale is made by dividing 19 main scale divisions into 20 parts. Least count of the main scale is 1mm. a) What is the least count of this vernier caliper. b) what is the uncertainty of this instrument. c) Describe zero errors associated with vernier calipers and reasons to occur zero errors.

PLEASE SHOW ALL CALCULATIONS AND EXPLANATION

A top-loading washing machine has a cylindrical tub that rotates about a vertical axis. The tub of one such machine starts from rest and reaches an angular speed of 2.0 rev/s in 7.0 s. The lid of the machine is then opened, which turns off the machine, and the tub slows to rest in 11.0 s. Through how many revolutions does the tub turn during this 18 s interval? Assume constant angular acceleration while it is starting and stopping.

Two charges are located in the ?–? plane. If ?1=−3.20 nC and is located at (?=0.00 m,?=0.640 m), and the second charge has magnitude of ?2=3.80 nC and is located at (?=1.50 m,?=0.550 m), calculate the ? and ? components, ?? and ??, of the electric field, ?⃗ , in component form at the origin, (0,0). The Coulomb force constant is 1/(4??0)=8.99×109 N⋅m2/C2.

A dipole moment, p = (2 Cm i) + (-5 Cm j) + (7 Cm k), is within an E = (-5 N/C i) + (6 N/C j) + (3 N/C k).

- Determine the potential energy stored by the dipole in the field.
- Determine the torque on the dipole by the field.
- Determine the angle between the dipole moment and the field.

explain how the rate of change of flux affects the induced E.M.F. in a conductor

A) What will a spring scale read for the weight of a 54-kg woman in an elevator that moves upward with constant speed 5.0 m/s?

B) What will a spring scale read for the weight of a 54-kg woman in an elevator that moves downward with constant speed 5.0 m/s?

C) What will a spring scale read for the weight of a 54-kg woman in an elevator that moves upward with acceleration 0.35g?

D) What will a spring scale read for the weight of a 54-kg woman in an elevator that moves downward with acceleration 0.35 g ?

E) What will a spring scale read for the weight of a 54-kg woman in an elevator that moves in free fall?

Three resistors are connected in series across a battery. The value of each resistance and its maximum power rating are as follows: 6.6Ω and 17.2 W, 34.6Ω and 12.0 W, and 20.0Ω and 12.6 W. (a) What is the greatest voltage that the battery can have without one of the resistors burning up? (b) How much power does the battery deliver to the circuit in (a)?

Hello,
I'm using Halliday and Resnick's Fundamentals of Physics, 10th edition. It has some equations in it that seem to contradict each other. I know the problem is with me though, not the equations. Electric potential energy is given as U=VQ (equation 24-3), where Q is charge and V is voltage. We also have the equation, Q=CV (equation 25-1), where C is capacitance. So, it looks like we could say U=CV^2 (substituting CV from 25-1 for Q in 24-3). I know that we cannot, since U=1/2CV^2 (equation 25-22), but I don't see where the problem in my reasoning is.... any help would be appreciated! (Barney style please!)   Thanks!

Darrell

Ball 1, with a mass of 159 g and traveling at 11.0 m/s , collides head on with ball 2, which has a mass of 324 g and is initially at rest. Assume that ball 1 is traveling to the right before the collision and that the collision is one dimensional.

What is the final velocity of ball 1 if the collision is perfectly elastic?

Answer: -3.76 m/s

What is the final velocity of ball 2 if the collision is perfectly elastic?

Answer: 7.24 m/s

What are the final velocities of the combination if the balls stick together?

Answer: 3.62

How much KE was lost when the balls stuck together?

Use Maple to solve the problem shown below. (I know, the math is pretty easy, but that's not the point. The point is to test the capabilities of BbLearn.) Save your Maple worksheet to a PDF file and upload it here.

Note: To enter Comments into your Maple Worksheet, precede the comment with the # symbol. For example:

>f:=a*x^2+b*x+c=0;#This is a quadratic polynomial

The first part (>f:=a*x^2+b*x+c=0; ) is the Maple expression, and the second part (#This is a quadratic polynomial) is a comment.

Problem:

Pt has a work function larger than almost any other metal, 6.35 eV. What is the longest wavelength of light that can dislodge an electron from Pt metal?