Physics - January 2007

2007-01-27 22:28:29 · 10 answers · asked by Shubham Agarwal 1

2007-01-27 22:13:07 · 4 answers · asked by Chocolate Strawberries. 4

2007-01-27 21:54:08 · 3 answers · asked by Blahblah. 1

A batter hits a 0.140-kg baseball that was approaching him at 40.0 m/s and, as a result, the ball leaves the bat at 30.0 m/s in the direction of the pitcher. What is the magnitude of the impulse delivered to the baseball?
a. 9.80 Ns
b. 1.40 Ns
c. 5.60 Ns
d. 7.00 Ns

2007-01-27 21:01:21 · 1 answers · asked by Banana28 1

In a collision between two unequal masses, how does the impulse imparted to the smaller mass by the larger mass compare with the impulse imparted to the larger mass by the smaller one?
a. It is larger.
b. It is smaller.
c. They are equal.
d. The answer depends on how fast they are moving

2007-01-27 21:00:46 · 1 answers · asked by Banana28 1

A 0.330-kg volleyball is thrown vertically downward with a speed of 0.150 m/s. It takes it 0.0655 s to reach the ground. What is the magnitude of its momentum just before it hits the ground?
a. 0.212 kg x m/s
b. 0.262 kg x m/s
c. 0.163 kg m/s
d. 0.0216 kg x m/s

2007-01-27 20:59:08 · 1 answers · asked by shaft0208 1

Two air track carts move along an air track towards each other. Cart A has a mass of 450 g and moves toward the right with a speed of 0.850 m/s and air track cart B has a mass of 300 g and moves toward the left with a speed of 1.12 m/s. What is the total momentum of the system?
a. 0.047 kg x m/s toward the right.
b. 0.719 kg x m/s toward the right.
c. 0.750 kg x m/s toward the right.
d. 0.750 kg m/s toward the left.

2007-01-27 20:57:52 · 1 answers · asked by shaft0208 1

What should the height of a slide in a park be so that a child will reach the bottom of the slide with a speed of 15.0 m/s? Use g = 10.0 m/s squared:
a. 22.5 m
b. 15.1 m
c. 11.3 m
d. 10.5 m

2007-01-27 20:55:11 · 1 answers · asked by SMS 1

The ratio of the potential energy to the kinetic energy of an object of mass m at a height of 40 m above ground level is 2:1. What is the speed of the object at that point? Use g = 10 m/s squared:
a. 10 m/s
b. 20 m/s
c. 30 m/s
d. 40 m/s

2007-01-27 20:54:38 · 2 answers · asked by SMS 1

A mass of 1.0 kg is pushed against a spring with a spring constant of 25 N/m. As a result, the spring is compressed by 20 cm. The mass is then released. What is the amount of potential energy acquired by the spring when it is compressed?
a. 5.0 J
b. 0.20 J
c. 0.50 J
d. 10 J

2007-01-27 20:53:42 · 2 answers · asked by SMS 1

An object of mass 20 kg is raised vertically through a distance of 8.0 m above ground level. Using g = 10 m/s squared what is the potential energy of this object at this position?
a. 160 N/m
b. 160 Nm
c. 1600 N/m
d. 1600 Nm

2007-01-27 20:52:59 · 1 answers · asked by SMS 1

An object of mass 4.0 kg is moved from a point A to a point C as follows: 0.80 m vertically from A to B, and then 0.60 m horizontally from B to C. What is the amount of work done as the object is moved from point A to C? Use g = 10 m/s squared.

a. 1.3 J from A to B and 16 J from B to C.

b. 2.2 J from A to B and 32 J from B to C.

c. 32 J from A to B and 0 J from B to C.

d. 4.0 J from A to B and 16 J from B to C.

2007-01-27 20:52:10 · 2 answers · asked by SMS 1

2007-01-27 20:42:23 · 7 answers · asked by Lalit V 1

Given the radius of Mt.Everest from the earth's core is 8448 m.

That is:
r = 8448 m

Since:
Fg = G (m1 x m2) / r x r
(where G is the gravity constant 6.67e-11)

This g is equivalent to mass times acceleration isn't it? (F=ma or F=mg)

So that gives me a force in the unit of Newtons.

But then, how do I get the acceleration of that obeject per se (at least even estimate it?)

Please and thank you!

2007-01-27 20:38:53 · 5 answers · asked by inthemaking 2

According to this equation, mass is equivalent to energy, and mass can be converted id into energy. But is the reverse also possible? Is it possible to convert energy into mass? If yes,then how (theoretically, as well as practically)? If no, then why?

2007-01-27 20:20:50 · 6 answers · asked by Kristada 2

If three resistors are placed in parallel branches and powered by a 12-volt battery, then the voltage drop across each one of the three resistors is 12 volts. A charge flowing through the circuit would only encounter one of these three resistors and thus encounter a single voltage drop of 12 volts.

if it flows in only one branch how come all the bulbs have lit up?

2007-01-27 19:27:22 · 5 answers · asked by catty 4

2007-01-27 19:14:44 · 3 answers · asked by Manoj K 1

In an insulated vessel, 250g of ice at 0 degC is added to 600g of water at 18 degC.

a) What is the final temperature of the system?
b) How much ice remains when the system reaches equilibrium?

For a, the correct answer is 0 degC, however I got a final temperature of 15.1 degC. I do not understand how 0 degC was achieved.

2007-01-27 19:01:53 · 1 answers · asked by Anonymous

I tried working this out a few times...couldn't seem to get the answer! Can anyone try it out for me?

A 42.5-kg chair is attached to a spring and allowed to oscillate. When the chair is empty the chair takes 1.30 s to make one complete vibration. But with a person sitting in it, with her feet off the floor, the chair now takes 2.54 s for one cycle.

What is the mass of the person?

2007-01-27 19:00:39 · 3 answers · asked by Anonymous

2007-01-27 18:24:33 · 6 answers · asked by jamoo 1

A 89 kg fullback, running at 8.2 m/s, collides in midair with a 129 kg defensive tackle moving in the opposite direction. Both players end up with zero speed.

(a) What was the fullback's momentum before the collision?

(b) What was the change in the fullback's momentum?

(c) What was the change in the tackle's momentum?

(d) What was the tackle's original momentum?

(e) How fast was the tackle moving originally?

2007-01-27 18:24:32 · 2 answers · asked by azndancer4life 1

If the secondary current from a 50 watt light supplied through a 240 volt to 12 volt transformer is approx 4 amps what is the input current on the 240 volt supply side.

2007-01-27 18:23:33 · 3 answers · asked by WM 2

If the background countrate is 1 per second and the countrate with the beta source present is only 3 per second, how long would you have to measure the background counts and how long would you have to measure the beta source counts in order to have 1% precision in the difference between the two countrates? x=3...P(m)=((x^m)/m!)(e^-x)

2007-01-27 18:09:03 · 1 answers · asked by chijliak 1

2007-01-27 17:31:30 · 12 answers · asked by natasha 1

A 20 gram bullet is fired horizontally into a 5 kg block of wood suspended by a long cord. The bullet sticks in the block. Determine the velocity of the bullet if the inelastic collision causes the block to swing 0.08m above its intial level.

2007-01-27 17:31:08 · 1 answers · asked by khenzkey_wawa08 1

(a)How much power does she expend? (b)What is her horsepower?

2007-01-27 17:13:34 · 1 answers · asked by Anonymous

How about positron or neutron
what is inside electron
what is the material of electron

2007-01-27 17:04:44 · 9 answers · asked by Mohsen J 2

what happens to the internal energy of water vapor in the air that condenses on the outside of a cold glass of water? Is work done or heat exchanged?

2007-01-27 16:50:16 · 3 answers · asked by TehEagle 1

2007-01-27 15:58:01 · 7 answers · asked by Optimist 1

2007-01-27 15:54:36 · 7 answers · asked by Anonymous