Two masses collide inelastically in two different kind of collisions. In the first collision, mass 1 with a mass of 11 kg is moving at 20.9 m/s in the positive x direction and collides with mass 2 with a mass of 4 kg moving at 11.9 m/s in the positive x direction.   In the second collision, mass 1 is moving at 20.9 m/s in the positive x direction and collides with mass 2 moving at 11.9 m/s in the negative x direction. If both collisions take place in a time of 0.36 seconds, how much more average force is exerted on mass 2 by mass 1 in the second collision as opposed to the first collision? Answer in Newtons.

Explain why measuring acceleration of the cart while it is going up and down the ramp is a more accurate procedure to determine g than just letting it accelerate down the ramp. Hint: Make 2 sketches showing all important forces acting along the ramp during the up and then down trip. Base your argument on these sketches.

Consider a fusion reaction in which a proton fuses with a neutron to form a deuterium nucleus. How much energy is released in this reaction?(The mass of the deuterium nucleus is 2.01355u)   MeV

I calculated these solutions myself but I have doubt in my answers, I'd appreciate some confirmation.

a. The U.S. average yield of corn is 153 bushels/acre.

Does this agree with the 2009 international average as

defined by the United Nation

Two point charges Q₁ = +4.00 nC and

Q₂ = −2.70 nC

are separated by 55.0 cm.

(a) What is the electric potential at a point midway between the charges?
V

(b) What is the potential energy of the pair of charges?
J

What is the significance of the algebraic sign of your answer?

Positive work must be done to separate the charges.Negative work must be done to separate the charges.  

In a experiment we did with electromagnets, we used only one battery with a certain voltage and didn't change it out. So did the current stay constant if we used the same battery because the voltage stayed constant????

The purpose of the experiment was to manipulate the number of winds to increase the magnetic field strength.

Thanks

  A 63.0-? resistor is connected in parallel with a 115.0-? resistor. This parallel group is connected in series with a 17.0-? resistor. The total combination is connected across a 15.0-V battery.

(a) Find the current in the 115.0-? resistor.
A

(b) Find the power dissipated in the 115.0-? resistor.
W

1. A potter's wheel is rotating around a vertical axis through its center at a frequency of 1.8rev/s . The wheel can be considered a uniform disk of mass 5.0kg and diameter 0.30m . The potter then throws a 3.2-kg chunk of clay, approximately shaped as a flat disk of radius 8.0cm , onto the center of the rotating wheel.

What is the frequency of the wheel after the clay sticks to it? Ignore friction.

Express your answer using two significant figures.

As discussed in the previous question, the second stage of the propulsion system is used to boost the spacecraft from Martian orbit into an interplanetary trajectory and return to Earth.

Knowing that the thrust generated by the second stage is 2620 N and the rocket exhaust velocity is 430 m/s; calculate the minimum amount of propellant needed to have a chance of returning to Earth. Assume that the thruster must be turned on for 2 minutes in order to reach the proper velocity.

Give your answer in kg.

Thank you for your time!

Explain what you understand from 'Ohm's law'. In about 50 words, explain practical consequences of Ohm's law, with examples from real life, as needed.

Problem 14.71 IP Standing Waves in the Human Ear The human ear canal is much like an organ pipe that is closed at one end (at the tympanic membrane or eardrum) and open at the other (Figure 1) . A typical ear canal has a length of about 2.4 cm.

Part A What are the fundamental frequency and wavelength of the ear canal? Express your answer using two significant figures. f1 =_______ Hz

Part B Express your answer using two significant figures. λ1 = _____cm

Part C Find the frequency and wavelength of the ear canal's third harmonic. (Recall that the third harmonic in this case is the standing wave with the second-lowest frequency.) Express your answer using two significant figures. f3 =_______ Hz

Part D Express your answer using two significant figures. λ3 =_____ cm

Part E Suppose a person has an ear canal that is shorter than 2.4 cm. Is the fundamental frequency of that person's ear canal greater than, less than, or the same as the value found in part A? Explain.

As an electron moves in the direction of the electric field lines...

Answer: It is moving from high potential to low potential and gaining electric potential energy.

Can someone explain why the electron is gaining electric potential energy if it is moving from high to low potential energy?

A 195-kg rugby player running east with a speed of 4.00 m/s tackles a 95.0-kg opponent running north with a speed of 4.5 m/s. Assume the tackle is a perfectly inelastic collision. (Assume that the +x-axis points towards the east and the +y-axis points towards the north.)

(a) What is the velocity of the players immediately after the tackle?

(b) What is the amount of mechanical energy lost during the collision?
______J

A 100.0 m rod with a diameter of 3.0mm has a charge of 1004.0C. What is the approximate electric field 2.0mm from the surface of the rod, not near either end?

A) 9.0*10¹¹ r N/C

B) - 9.0*10¹¹ r N/C

C) - 5.2*10¹³ r N/C

D) 5.2*10¹³ r N/C

The answer is D, I am not sure how they got that answer, can you please explain and show your work. Thanks in advance