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over 11 years ago

# When University of Calcutta was founded?

Hi Everyone! I wouldn't be bothering but this seems far above my caliber. When University of Calcutta was founded?
6
over 11 years ago

# When University of Calcutta was founded?

Hi Everyone! I wouldn't be bothering but this seems far above my caliber. When University of Calcutta was founded?
0
over 11 years ago

# "What is the equivalent resistance of the resistors when they are connected? "

"1)A circuit contains three resistors of values: 24 ohms, 110 ohms, and 76 ohms. What is the equivalent resistance of the resistors when they are connected:a) In series?b) In parallel?2)If the three resistors from problem 4 are connected in parallel with a 12 V power supply, what is the current through the 24 ohm resistor?"
6
over 11 years ago

# Can cars "fly" over pot holes if they go fast enough?

What I mean is the driver nor the car will feel the pot holes when they go over them. So I'm wondering if it's possible at high speeds.
6
over 11 years ago

# Physics problem walking 30 blocks?

You are walking rapidly(4mph) how long would it take to walk 30 blocks in minutes?(30 blocks is equal to 1/10th of a mile)
6
over 11 years ago

"Calculate the magnitude of the electric field at the centre of a square 8.0 cm on a side, if one corner is occupied by a 14.0 µC charge and the other three are occupied by 1.0 µC charges.(Hint: what would the field be if they were all equal?)n.b. give your answer in N/Chint:If all of the charges are equal, there will be no field at the centre. Hence it is much easier to replace the different charge by the difference between it and one of the others, and you can then regard this as a problem with just a single charge.i tried but couldnt get the answer. could u please help/"
6
over 11 years ago

# Butter in the microwave?

"Basically I've been wondering why putting butter in the microwave heats the inside and not the outside. Meanwhile every website I have checked says that microwaves don't heat from the onside out.Could it be that the temperature to start with (on the outside) was lower or had ( doubtful) less water/fat content therefore heated up less?"
6
over 11 years ago

# Difference between work done by a spring and work on a spring?

what's the difference in calculating the work done by a spring and the work done on a spring during compression
5
over 11 years ago

# Why do we need infinite force to keep an object moving at the speed of light?

"In absolute vacuum, there is nothing to oppose the motion of the object. So, once an object reaches the speed of light (theoretically), why should we have to give it infinite force to maintain that speed? It should move at the speed of light, due to inertia, without the absence of any force, as stated by Newton's Law.Could you please explain me this part of the theory of relativity?"
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over 11 years ago

# What is your opinion on the second law of thermodynamics?

what is your opinon of the second law of thermodynamics and entropy?
6
over 11 years ago

# LAST 10 MINUTES. pLEASE help.the electron starts from rest at the negatively charged plate, how long does ?

An electron is between two plates with a field E = 575.0 N/C. If the plates are separated by a distance 0.7 cm, and the electron starts from rest at the negatively charged plate, how long does it take to travel from one to the other?
5
over 11 years ago

# What is the x-component of the Electric field at point P?

"A line of charge with a uniform charge density -22.00 nC/m lies along the y axis in the region 0 ≤ y ≤ 0.50 m. Calculate the electric field of this line of charge at point P on the x-axis a distance 0.60 m from the origin.What is the x-component of the Electric field at point P?http://www.flickr.com/photos/85663959@N08/ heres a pictureIm really lost. I think you have to do a intergral between 0-.5. But i have no idea what the forumla/setup is.But im not even sure if thats the correct way to go about things"
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over 11 years ago
over 11 years ago

# How is adiabatic compression related to order and disorder?

"During adiabatic compression the entropy doesn't change. How do we explain that with order or disorder, based on the fact, that entropy presents disorder?I know that a more disorderly system has a greater entropy, and during compression, the volume gets smaller, thus the system will have a bigger order and the entropy will be smaller. But if the entropy doesn't change, that means it is an adiabatic reversible process...yet I don't know how to connect the ""no change of entropy"" to order/disorder."
6
over 11 years ago
over 11 years ago

# 5 less than 28% of 292?

Hi Everyone! I wouldn't be bothering but this seems far above my caliber.
6
over 11 years ago

# If black is the absence of color, how do we see black?

I understand the color we see is what is the pigment NOT reflected. But, since black is the absence of color, what is being reflected?
6
over 11 years ago

# At a distance of 45m from a traffic light, a car traveling 15 m/sec is brought to a stop?

"At a distance of 45m from a traffic light, a car traveling 15 m/sec is brought to a stop at a constant deceleration.a. What is the value of deceleration?b. How far has the car moved when its speed has been reduced to 3m/sec?c. How many seconds would the car take to come to a full stop?"
6
over 11 years ago

# If she jumps off a 140 cm high table, how far does Earth move toward her as she falls?

"Your friend’s mass is 62kg. If she jumps off a 140 cm high table, how far does Earth move toward her as she falls?Im not quite sure on how to start this problem. According to Newton's 3rd law, shouldn't the earth move to her 70cm and she moves toward the earth 70cm? Or is that too simple of an answer? I have no idea what to do with the mass of the friend."
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over 11 years ago

# What mathematics would I need to know for theoretical physics?

I am much smarter than the other students in my school and am immensely bored in my high school precalculus class. Because of this, I have resorted to self-studying more advanced topics. I want to be a physicist (ideally a theoretical physicist), but I am going to a governor's school this summer about physics and I don't want it to be really boring because I know the material already, so I have taught myself required math instead. My math background is up to single and multivariable calculus, and I have also dabbled in but by no means mastered differential equations. Thanks in advance for any answers and suggestions to good books teaching the subject would be much appreciated.
6
over 11 years ago
over 11 years ago

# Find the net force acting on particle 3 due to the presence of the other two particles.?

"To practice Problem-Solving Strategy 21.1 Coulomb's Law.Three charged particles are placed at each of three corners of an equilateral triangle whose sides are of length 2.2cm. Two of the particles have a negative charge: q1= -7.2nC and q2 = -14.4nC . The remaining particle has a positive charge, q3 = 8.0nC . What is the net electric force acting on particle 3 due to particle 1 and particle 2?Part BFind the net force acting on particle 3 due to the presence of the other two particles. Report you answer as a magnitude and a direction measured from the positive x axis.How do I solve this?"
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over 11 years ago
over 11 years ago

# Physics help please asking for speed of a cart on an inclined plane?

"A cart with a mass of 2.14 kg is placed on a frictionless ramp as pictured above. If the cart at the top of the ramp is allowed to roll 8.9 meters along the ramp, the speed of the cart would be ______ m/s. Enter your answer with two decimal places.this is a right triangle so it's a 30-60-90"
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over 11 years ago

# What are the action-reaction forces between the car and the ground?

Hi Everyone! I wouldn't be bothering but this seems far above my caliber.
7
over 11 years ago

# What metric units are used to mesure mass?

I have an assignment due next week. Please provide the relevant solution.
7
over 11 years ago

# How to calculate amount of energy absorbed?

"A 30kg child abosrbs 3 mG of radiation. How much energy did the child absorb?I worked it out and got 0.1but the answer was something like 1 x 10 ^ -1something like that, how do I do it! Please help"
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over 11 years ago

# PHYSICS HELP!!! What must be the current through an electrolytic cell to produce 1.0kg of Cl2 gas in 29 hours?

"Chlorine gas (Cl2) can be produced from a solution containing Cl− ions (i.e., from Na+,Cl−) by electrolysis.What must be the current through an electrolytic cell to produce 1.0 kg of Cl2 gas in 29 hours? The fundamental charge is 1.602 × 10^−19 C, Avogadro’s number is 6.022 × 10^23, and the atomic mass of chlorine is 35.5 g/mol.Answer in units of APlease help!!!"
6
over 11 years ago

A mortar* crew is positioned near the top of a steep hill. Enemy forces are charging up the hill and it is necessary for the crew to spring into action. Angling the mortar at an angle of theta= 62.0 degrees, the crew fires the shell at a muzzle velocity of 127 feet per second. How far down the hill does the shell strike if the hill subtends an angle phi= 33.0 degrees from the horizontal? (Ignore air friction) How long will the mortar shell remain in the air? How fast will the shell be traveling when it hits the ground? The answer must be in terms of meters.
6
over 11 years ago

# Having a problem with force of repulsion?

"For which of the following positive charges, separated by the distance shown, will the electrostatic force of repulsion be smallest?A) +2q and +1q at 2 metersB) +1q and +2q at 1metersC) +2q and +2q at 2 metersD) +2q and +3q at 3 metersThe answer is a but I want to see the math"
6
over 11 years ago

# A table with four legs has a mass of 20 kg. A box with a mass of 50 kg sets on top of the table. How much forc?

HELP! I really don't understand this problem, please explain in detail, if you can. Thanks :)
6
over 11 years ago

# How is E=mc2 Used today?

What modern Inventions, technology, Ideas, have stemmed from the E=mc2 equation?
6
over 11 years ago

# You are eating lunch at your favorite cafe and your friend calls and says he wants to meet you.?

"You are eating lunch at your favorite cafe and your friend calls and says he wants to meet you. He is calling from a city 165 miles away and wants to meet you somewhere between the two locations. He says he will start driving right away, but you need 33.0 minutes to finish your lunch before you can begin driving. If your friend plans to drive at 65.0 mph and you plan to drive at 50.0 mph,A) how long will your friend be driving before he meets you? (Ignore acceleration and assume the highway forms a straight line.)B) How far will you have traveled by the time you meet him?"
1
over 11 years ago

# Confused I thought anything positive was never spontaneous please explain? P?

"The change in Gibbs energy for a reaction at constant temperature is given by the equation above. G=H-TS. H=+2H= +20,000 J and S=+ 100 J/K, which of the following is true about the reaction?A) it is never spontaneousB) it is always spontaneous at any tempC) it is spont. At temp. Above 200k only.D) it is spont. At temps. Below 200K onlyThe answer is c but I need clarificationAsked by liberian princess 41 minutes ago 4 days left to answer."
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over 11 years ago
over 11 years ago

# A hockey puck is sliding across a frozen pond with an initial speed of 9.9 ms.?

"It comes to rest after sliding a distance of 37.6 m. What is the coefficient of kinetic friction between the puck and the ice?Physics problem. Just looking for a little help."
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over 11 years ago

# A m=4 gram object is accelerated at a rate of a=2.7 m/s^2.?

"A m=4 gram object is accelerated at a rate of a=2.7 m/s^2. What is the magnitude of 10^3×F where F is force the object experience? Express the answer with one decimal place.Can anyone explain to me how to solve this equation? I really stink at physics and need help. Explanations are really appreciated."
1
over 11 years ago

# How does the number of photons relate to this question?

"How does the number of photons relate to the equation E = hv ?A laser pulse of light with a frequency of 5.64 × 109 Hz contains 6210 photons. Calculate the energy in J of the pulse. Express answer in scientific notation.The way I see it, they give you frequency and that's all you need to solve for E in the equation E = hv."
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over 11 years ago

# Can someone explain this physics motion problem?

".My physics professor did a demo and tried to explain this concept, however, I still don't seem to understand it. The (small) demo went like this:A mini minecart with a small ball placed in it was placed on a rail (in which it will be pushed), and along the rail there was a ""cave"" like enclosure (like a roof that barely lets the minecart pass under it). A bit before the enclosure is a mechanism that shoots the ball into the air, and as the minecart progresses under the enclosure, the ball is in the air doing a parabolic motion in which it lands right back into the minecart after it has past the enclosure.It makes sense that this happens - after all, you throw a ball up in the air it goes right back in your hand right in the same spot. But where I'm failing at, is explaining this intuition with physics concepts.So the question is, WHY, in terms of physics, does the ball land right in the same spot in the minecart demo? Why is there a parabolic motion? Why does the ball move as opposed to staying in place and fall back down BEHIND the minecart?Our professor said something about the x and y components don't effect each other, and that's why it lands in the same spot (i.e. the y component of the position vector is in the same spot, and thus delta y is 0)."
5
over 11 years ago
over 11 years ago

# How far away must one move to reduce the sound level?

The sound level 3 meters away from a jackhammer is 110 db. Suppose that the sound is radiated uniformly over a hemisphere. How far away must one move to reduce the sound level to 60 db?
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over 11 years ago

# A jet flies at a constant speed of 1200 km/hr...?

"A jet flies at a constant speed of 1200 km/hr for 107.8 minutes. What distance does the jet cover?Seems simple? Got 2156 km/hr, but the answer is supposedly 2000 km/hr.Why is that?"
6
over 11 years ago
over 11 years ago

# Find the angular velocity in rad/min of an 8 ft long windmill blade that is spinning at a rate of 270 rev/hr?

"Find the angular velocity in rad/min of an 8 ft long windmill blade that is spinning at arate of 270 rev/hr."
6
over 11 years ago

# A tube of length L lies along the x axis. It is sealed at the end x=L?

A tube of length L lies along the x axis. It is sealed at the end x=L and fitted with a position at the end x=0. The piston vibrates in the x direction with a displacement amplitude: Δx=x0cosΩt. Find the pressure and velocity v(x,t) of the fluid in the resulting sound wave inside the pipe. For what L is the amplitude of the sound a maximum.
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