Physics - February 2007

1) If a car traveling at 58 km/h will skid 22 m when its brakes lock, how far will it skid if it is traveling at 120 km/h when its brakes lock?

2) A certain car can go from 0 to 95 km/h in 7 s. If the engine delivered twice the power to the wheels, how many seconds would it take?

2007-02-18 12:37:00 · 2 answers · asked by Jane A 3

2007-02-18 12:19:15 · 2 answers · asked by Art Student 2

A 13.0 kg object undergoes an acceleration of 1.9 m/s2.

(a) What is the magnitude of the resultant force acting on it?
___N
(b) If this same force is applied to a 26.0 kg object, what acceleration is produced?
____m/s2

2007-02-18 12:16:16 · 1 answers · asked by Anonymous

I have eight lights flowing in parallel to a 1.1E2-V source by two long leads of total resistance.

If the resistance of each equals 500ohms and the current equals 2.2E-1 A what percentage of the total power is wasted in the leads.

I'm lost...any help would be great! Thanks!

2007-02-18 12:01:13 · 2 answers · asked by belaine57 1

Please help me with the following equation. I am having difficulty solving it. So far I've got:
10 cm = 1 m

Inertia = MR^2

I = (3.0kg)(0.1m)^2 = .03 kg*m

A thin hoop with a radius of 10 cm and a mass of 3.0 kg is rotating about its center with an angular speed of 3.5 rad/s. What is its kinetic energy?

a. 0.18 J
b. 0.092 J
c. 1.05 J
d. 0.53 J

2007-02-18 12:00:18 · 4 answers · asked by Banana28 1

What is the magnitude of the gravitational force between the earth (5.98x10^25kg) and the moon (7.35x10^22kg)?

2007-02-18 11:54:11 · 5 answers · asked by ellyvstheworld 1

I found 319 questions just like this one. " Why do people say evolution is only a theory, gravity is only a theory too." It only takes a few seconds to look up Newton and the Law of Gravity on the internet but it takes even less time to jump off your roof and find out that you will land on the ground every time. Imagine that! You could discover gravity just like Newton did over 300 years ago. Amazing!

http://en.wikipedia.org/wiki/Gravity

2007-02-18 11:42:34 · 7 answers · asked by Specialist McKay 4

2007-02-18 10:56:16 · 1 answers · asked by Joy o 1

its like they all sort of merge into each other. I'd just like to know what others think about it.

2007-02-18 10:23:31 · 23 answers · asked by bonnie-bee 2

2007-02-18 10:10:02 · 2 answers · asked by Katy P 1

Any hints would be good :)

A block hangs from a spring and is set into vertical oscillation with a frequency of 1.20 Hz.
Calculate the extension of the spring when the block is at the equilibrium position.

2007-02-18 09:16:14 · 2 answers · asked by poppa 1

2007-02-18 09:11:36 · 3 answers · asked by tjcsonofallnations 3

The gravitational force on loop is downward. A rectangular loop with dimensions (horizontal=.2m) x (vertical=.46m), is suspended by a string, and the lower horizontal section is immersed in a magnetic field. HOw must the current flow in the loop so that tension in the supporting string is increased? The gravitational force on the loop is downward.

2007-02-18 09:11:07 · 1 answers · asked by beehappinow 1

It is for Physics and I'm freakin. must be for bigger than a triangle 19.5 inches by 19.5 inches? HELP!!!!!!!!!!!!

2007-02-18 08:54:21 · 3 answers · asked by megmaker13 1

If a current of 1.1 A is maintained in the loop, what is the magnitude of the magnetic field required to produce a tension of 0.039 N in the supporting string for a negligible gravitational force?

2007-02-18 08:49:08 · 1 answers · asked by beehappinow 1

2007-02-18 08:42:42 · 9 answers · asked by scotty 89 1

A driver in a car traveling at a speed of 49.7 units mi/h
sees a deer 105 m away on the road.

Calculate the minimum constant acceleration that is necessary
for the car to stop without hitting the deer (assuming that
the deer does not move in the meantime).
Answer in units of m/s^2 .

2007-02-18 08:41:20 · 3 answers · asked by KayJ 1

A 1.7 kg body is at rest on a frictionless horizontal air track when a horizontal force F acting in the positive direction of an x axis along the track is applied to the body. A stroboscopic graph of the position of the body as it slides to the right. The force F is applied to the body at t = 0, and the graph records the position of the body at 0.50 s intervals. How much work is done on the body by the applied force F between t = 0 and t = 2.0 s? (HINT: Find the average acceleration over t = 0 to t = 2.0 s.)

the body is at 0.004 at 0.5s, 0.2 at 1s, 0.404 at 1.5s, and 0.8 at 2s

2007-02-18 08:31:53 · 1 answers · asked by x2carlosp 2

A 3.8 kg penguin sits on a 10 kg sled. A horizontal force of 45 N is applied to the sled, but the penguin attempts to impede the motion by holding onto a cord attached to a wall. The coefficient of kinetic friction between the sled and snow, as well as that between the sled and the penguin, is 0.20.

I drew and FBD but I don't understand how to find the tension of the cord. I know I multiply .20 with something but I dont know what. Thanks.

2007-02-18 08:28:52 · 1 answers · asked by Kacey L 1

calculate the binding energy of the last neutron in the calcium mass number 43 & atomic number 20 nucleus. ( hint u shoul d compare the mass of calcium atomice number 20 & mass # 42 plus the mass of a neutron,


PLz show me how to do it. Promise to give u 10 points if u help me with the question, THNX

2007-02-18 08:25:58 · 1 answers · asked by mitu 2

Electricity can be a hazard in hospitals, particularly to patients who are connected to electrodes, such as an ECG. For example, suppose that the motor of a motorized bed shorts out to the bed frame, and the bed frame's connection to a ground has broken (or was not there in the first place). If a nurse touches the bed and the patient at the same time, she becomes a conductor and a complete circuit can be made through the patient to ground through the ECG apparatus. (where V = 220 V and R (the nurse) = 1.00E4 . Calculate the current through the patient.

2007-02-18 08:10:18 · 5 answers · asked by webogirl 2

and also the wave lengths if u hav them

2007-02-18 08:07:23 · 3 answers · asked by z 2

I got some information 'bout it that it can be done only when you have a large amount of energy? Please tell me a mechanism through which we can convert energy into matter or antimatter.

2007-02-18 07:54:53 · 2 answers · asked by Suhel 1

imagine there's a trapezoidal prism

but the trapezoids on the sides are slanted.

so as a result, the top of the spae is smaller due to the slant.

so wat is that shape called?

2007-02-18 07:53:40 · 1 answers · asked by *believe_it* 4

A person walks 25 m west and then 45 m at an angle of
60degrees north of east.

What is the magnitude of the total displacement?

2007-02-18 07:49:09 · 3 answers · asked by KayJ 1

Suppose that the switch has been closed for a length of time sufficiently long enough for the capacitor to become fully charged. (R = 11.0 k, R2 = 16.0 k, R3 = 5.00 k, V = 9.40 V) http://www.webassign.net/sercp/p18-50alt.gif
Find the steady-state current for each resistor.

2007-02-18 07:40:18 · 2 answers · asked by Shelia 1

Is age and temperature scalar quantities, vector quantities or neither?

2007-02-18 07:40:09 · 5 answers · asked by angelgirl 2

1. Draw magnetic field lines around a straight section of wire carrying a current horizontally to the left.

2. In what direction are the magnetic field lines surrounding a straight wire carrying a current that is moving directly toward you?

3. a horseshoe magnet is held vertically with the north pole on the left and south pole on the right. a wire passes between the poles, equidistant from them, and carries a current directly away from you. in what direction is the force on the wire?

4. after you rub comb and silk, which one is positive? why?

5.when an electroscope is charged, two leaves repel each other and remain at an angle. what balances the electric force of the repulsion so that the leaves dont separate further?

6. when an electric cell is connected to a circuit, electrons flow away from the negative terminal in the circuit. but within the cell, electrons flow to the negative terminal. Explain

7. can copper wire and aluminum wire of the same length have same R?

2007-02-18 07:11:16 · 4 answers · asked by Anonymous

there was a program on uk tv called eureka. on this show they made a hologam maker. i am pretty good at constructing things and i have knowledge of photography. my daughter is at high school and i think it would be a neat project for her to help with.

2007-02-18 07:06:38 · 7 answers · asked by Anonymous

2007-02-18 06:56:59 · 11 answers · asked by liz s 2