Physics - October 2007

2007-10-31 12:47:40 · 1 answers · asked by adidasblack16 1

Im not gonna aim at ppl but does it hurt if on flys and hits you?

2007-10-31 12:43:33 · 3 answers · asked by tommy_li05 1

please filll in the blank

2007-10-31 12:31:51 · 2 answers · asked by ABC 2

A skateboard track has the form of a circular arc with a 4.25 m radius, extending to an angle of 90.0° relative to the vertical on either side of the lowest point, as shown in Figure 8-27. A 63.0 kg skateboarder starts from rest at the top of the circular arc.
http://i214.photobucket.com/albums/cc30/bkoz319/08-24alt.gif

(a)What is the normal force exerted on the skateboarder at the bottom of the circular arc?
___kN




Thanks for your time!!!!

2007-10-31 12:31:42 · 1 answers · asked by SurferGirl9 1

There are 14.7 pounds of pressure weighing down on us Why are we not crushed by the weight of the atmosphere ?

2007-10-31 11:43:15 · 3 answers · asked by liltchaser 2

The Mars Pathfinder is designed to drop the vehicle's instrument package from a height of 20 meters above the Martian surface, after the speed of the probe has been brought to zero by a combination parachute-rocket system at that height. To cushion the landing, giant air bags surround the package. The mass of mars is 0.1074 times that of earth and the radius of mars is 0.5282 that of earth. FInd a) the accerleration due to gravity at the surface of Mars, b) and how long it takes for the instrument package to fall the last 20 meters.

help please!

2007-10-31 11:36:29 · 2 answers · asked by sccrsweetie 2

We learned in class today and I just cant understand it when Im on my own but he still collects it before showing us how to do it so I guess I just need to ask on here...

1)... he did this by lifting and holding above his head a barbell whose mass was 253 kg. His mass at the time was roughly 113kg. Draw a free-body diagram and the forces in the problem. *Calculate the normal force exerted on each of his feet during the time he was holding the barbell.*

2)A gorillas mass is about 3.10x10^2 kg. Suppose it hangs from two vines, each of which makes an angle of 30 with vertical. Draw the diagram with forces and *find the magnitude of the force of tension in each vine. What would happen to the tensions if the upper ends of the vines were farther apart?*

2007-10-31 11:23:14 · 1 answers · asked by shepey11 2

Betty weighs 436N and she is sitting on a playground swing seat that hangs 0.46 m above the ground. Tom pulls the swing back and releases it when the seat is 1 m above the ground. the acceleration of gravity is 9.8 m/s/s.

how fast is Betty moving when the swing passes through its lowest position? answer in units of m/s.

if Betty moves through the lowest point at 1.4 m/s, what is the magnitude of the work done on the swing by friction? answer in units of J

2007-10-31 11:22:00 · 1 answers · asked by lilprincess_2good4u 1

a bead slides without friction around a loop-the-loop. the bead is released from a height of 24.7 m fromt he bottom of the loop-the-loop which has a radius 9m. the acceleration of gravity is 9.8m/s/s.

what is its speed at the top of the loop-the-loop? answer in units of m/s.

2007-10-31 11:17:02 · 2 answers · asked by lilprincess_2good4u 1

A car traveling on a flat (unbanked) circular track accelerates uniformly from rest with a tangential acceleration of 2.10 m/s^2. The car makes it .25 of the way around the circle before it skids off the track. What is the coefficient of static friction between the car and track?

The tires of a 1475 kg car are 0.591 m in diameter and the coefficients of friction with the road surface are µs = 0.8 and µk = 0.6. Assuming that the weight is evenly distributed on the four wheels, whats the maximum torque that can be exerted by the engine on driving wheel such that the wheel does not spin. Suppose that the car is at rest.

A bus is designed to draw its power from a rotating flywheel that is brought up to its maximum rate of rotation (3060 rev/min) by an electric motor. The flywheel is a solid cylinder with a mass of 1100 kg and diameter 1.03 m. If the bus requires an average power of 9.1 kW, how long does the flywheel rotate?

2007-10-31 11:04:36 · 2 answers · asked by niceguy0789 2

How does it affect our lives

2007-10-31 10:50:17 · 4 answers · asked by Anonymous

A drunk driver strikes a parked car. During the collision the cars become entangled and slide to a stop together. The drunk driver's car has a total mass of 742 kg, and the parked car has a total mass of 776 kg. If the cars slide 18 m before coming to rest, how fast was the drunk driver going? The coefficient of sliding friction between the tires and the road is 0.59.

Err any ideas?

2007-10-31 10:42:04 · 1 answers · asked by Anonymous

do they stay put or do they start bumpin' uglies.

2007-10-31 10:38:53 · 2 answers · asked by keyahnoo 2

2007-10-31 10:29:06 · 3 answers · asked by shinigami100 1

2007-10-31 10:25:05 · 7 answers · asked by alik_det 1

On a level road with its brakes on, the shortest distance in which a car traveling with 81 km/hr can stop is 94 m. This shortest distance occurs when the driver uses anti-lock brakes which means that that the car brakes without skidding.

a) What is the magnitude of the acceleration of the car?

|a| = 2.69 m/s2


b) What is the coefficient of friction between the tires and the pavement?

µ =

c) How steep a hill can the car park on? (Give the angle to horizontal).

Angle =


I can't get parts b and c for this problem. Can anybody show me how to calculate µ and the maximum angle?

2007-10-31 09:31:30 · 2 answers · asked by Guinness 3

As I understand it a quantum computer is a machine built under the foundations of Quantum Mechanics that would make the circuits so small that they can be in more than one place at a time (the miracle of minaturization is reaching it's limits on how small a transistor can get).

2007-10-31 09:06:03 · 3 answers · asked by primalclaws1974 6

i'm confused can someone tell me the difference between fision and fusion...?
i know we have nuclear power...which is fision...???

2007-10-31 09:00:27 · 10 answers · asked by Anonymous

Four 1.8 kg masses are located at the corners of a square 1.00 m on each side. Find the magnitude and direction of the gravitational force on a fifth 1.8 kg mass placed at the midpoint of the bottom side of the square.

2007-10-31 08:56:09 · 2 answers · asked by matt c 1

Three particales are located in a coordinatet system...
The mass 3kg is located at the origin.
The mass 6kg is located 10 meters on the x coordinate, and the mass 9 kg is located 6 meters on the y coordinate.

Find the distance of the center of gravity from the origin.

2007-10-31 08:43:57 · 1 answers · asked by Anonymous

Well I did this lab and need help because I am so confused I used a spectrometer and a helium lamp. I have to calculate d=m*wavelength / sin theta. For violet the left angle is 172 and 20 minutes and the right angle is 187 and 15 minutes and the wavelegth is 447.2 nanometers. What I don't understand is that how do I get m (integer that refers to the order of diffraction)? And when dividing by sin theta (180 degrees) do I change it to radians? Please if you have ever done this lab or know someone who has taken physics could you ask them.

2007-10-31 08:20:10 · 1 answers · asked by glance 3

Hi, could you help me with this question and also explain the steps, thanks!

A uniform semicircular lamina is suspended from an end point of its diameter. Assuming that it hangs freely under gravity, calculate in radians the angle between the diameter and the vertical.

2007-10-31 07:30:12 · 1 answers · asked by clueless 1

2007-10-31 07:26:31 · 2 answers · asked by John T 1

2007-10-31 07:24:46 · 2 answers · asked by John T 1

2007-10-31 07:16:08 · 3 answers · asked by Anonymous

1000 0000 0000 1000

2007-10-31 07:15:58 · 1 answers · asked by purple21 1

2007-10-31 07:03:32 · 5 answers · asked by Anonymous

Two gliders have different masses. Glider 2 weighs 3 times as much as glider 1. Assuming glider 2 to be initially at rest as before, describe the final momentum in terms of the initial momentum, both in magnitude and direction for all vector quantities. Approximate the magnitudes of momentum.

m_2=3m_1

u_2=0

2007-10-31 07:02:25 · 1 answers · asked by pearlnruby89 1

2007-10-31 07:02:06 · 6 answers · asked by Anonymous

A toaster using a Nichrome heating element operates on 120V. When it is switched on at 20.0 Celsius, the heating element carries an initial current of 1.35A. A few seconds later the current reaches the steady value of 1.23A.

a) What is the final temperature of the element? The average value of the temperature coefficient of resistivity for Nichrome over the temperature range is 4.5*10^-4 (1/Celsius).

b) What is the power dissipated in the heating element initially?

c) What is the power dissipated in the heating element when the current reaches a steady value?

Appreciate the help :)

2007-10-31 06:26:44 · 1 answers · asked by Hannah 4