a-How much heat is required to convert 5.0 kg of ice from a temperature of -10 C to water vapor at a temperature of 220F? b-You have 200 g of coffee at 55 C, Coffee has the same specific heat as water. How much ice at -5 C do you need to add in order to reduce the coffee’s temperature to 27C.
In: Physics
Having aced your introductory physics course, you are hired as a summer intern at NASA. You are sent as part of a team to explore the possibility of mining iron from a small, airless spherical asteroid with a radius of 469 km and a surface acceleration of 3.4 m/sec2.
4)How far will the 3 kg rock go if it leaves the asteroids surface with a vertical velocity of 1000 m/sec?"
(Not sure why the answer isn't 147059 m. I used vf^2 = vi^2 + 2ah. 0 = 1000^2 + 2 * -3.4 m/s * h. h = (1000^2) / (2*3.4) = 147059 m.)
5)What will the speed of the 6 kg rock be at the surface of the asteroid if it is dropped from a point 1000km above the surface of the asteroid?
(Not sure why the answer isn't 2608 m/s. I did v=sqrt(2ah) = sqrt(2*3.4*1000000).)
In: Physics
A 5.00-kg bullet moving with an initial speed of Vi= 400 m/s is fired into and passes through a 1.00-kg block as shown in the Figure. The block, initially at rest on a frictionless, horizontal surface, is connected to a spring with force constant 1000 N/m. The block moves d = 5.00 cm to the right after impact before being brought to rest by the spring. Find:
The speed at which the bullet emerges from the block.
The kinetic energy lost (the amount of intial kinetic energy of the bullet that is converted into internal energy, i.e. heat, in the bullet-block system) during the collison.
In: Physics
1. Compute the mechanical work done by the helicopter on lifting a 1,200-kg house to a
height of 800m. Show all your work.
2. What maximum speed (in miles per hour) can a 1,800-kg, 160-horse-power car theoretically develop moving up a 30-degree slope? Show all your work.
3. A boat of mass 720kg (including passengers) floats stationary on water before an 80-kg woman jumps into it horizontally at 5m/s. At what speed does the boat begin to move? Show all your work.
In: Physics
white printer paper have an equal mass, but unequal surface area
coffee filters have an equal surface area with unequal in mass
how does mass and surface area affect the free fall of an object? do theses qualities affect the pull of gravity or resistance of the air?
connect the paper and coffee filters object to 1st, 2nd newton law and friction
In: Physics
A railroad car of mass 2.20 ✕ 104 kg moving at 5.00 m/s collides and couples with two coupled railroad cars, each of the same mass as the single car and moving in the same direction at 1.20 m/s.
(a) What is the speed of the three coupled cars after the
collision?
_________________m/s
(b) How much kinetic energy is lost in the collision?
________________J
In: Physics
The normalized wave function of an electron in a linear accelerator is ψ = (cos χ)eikx + (sin χ)e–ikx, where χ (chi) is a parameter. (a) What is the probability that the electron will be found with a linear momentum (a) +kħ, (b) −kħ? (c) What form would the wave function have if it were 90% certain that the electron had linear momentum +kħ? (d) Evaluate the kinetic energy of the electron.
In: Physics
Bart and Nelson challenged each other to a bumper car game. Bart, whose car had a mass of 120 kg (with him in it), traveled west at a velocity of 9 m/s. Nelson and his car had a total mass of 150 kg traveled a velocity of 7 m/s east, heading towards Bart. The two had a head-on collision. Use the frame of reference in which the east is positive.
a) If Bart left the collision at a velocity of 7 m/s east, what velocity did Nelson leave with?
b) Determine the total kinetic energy for Bart and Nelson before the collision. Determine the total kinetic energy after the collision.
c) Instead of heading towards each other, Bart was going 9 m/s east following behind Nelson, whose velocity is still 7 m/s east. At what velocity would Bart travel at after the collision if Nelson left the collision with a velocity of 7 m/s east?
In: Physics
Show how the wave function of the even states of a particle in an infinite well extending from x=-L/2 to x=L/2 evolve in time. Details!
In: Physics
5) A solenoid passes through the x-y plane. A charge of +5 Coulombs with a mass of 5 x 10-7 kg moving at 5 m/s (in the x-y plane) is placed in the solenoid. Due to the magnetic field produced by the solenoid, the charge moves counter-clockwise in a circle at a frequency of 34 Hz. The charge is removed and a circular wire wound 3 times with a radius of 0.6 meters is placed in the solenoid. If the total magnetic field at the center of the circular is zero, what is the amount and direction of the current in the circular wire in amps? Indicate clockwise by a negative sign (negative answer) and don't enter a sign for counter-clockwise.
In: Physics
In: Physics
A rocket has an initial mass of 28500 kg, of which 20% is the payload (i.e., the mass of the rocket minus the fuel). It burns fuel at a rate of 195 kg/s and exhausts its gas at a relative speed of 1.5 km/s.
(a) Find the thrust of the rocket.
kN
(b) Find the time until burnout.
s
(c) Find its final speed assuming it moves upward near the surface
of the earth where the gravitational field g is
constant.
km/s
In: Physics
1.Answer the following questions
A) Describe how the molecules in a gas produce an emission spectrum. How is this useful in astronomy if we assume that the laws of physics are the same everywhere?
B) Why was the uniform expansion model adopted? How does this lead to a necessary differentiation between classical and cosmological redshift
In: Physics
After they completely run out of fuel, all stars leave behind one of three objects, which do not usually do any more nuclear fusion. What are these three objects? Give the name of each and quick description.
In: Physics
A flywheel in a motor is spinning at 540.0 rpm when a power failure suddenly occurs. The flywheel has mass 40.0 kg and diameter 75.0 cm. The power is off for 36.0 s, and during this time the flywheel slows down uniformly due to friction in its axle bearings. During the time the power is off, the flywheel makes 230.0 complete revolutions.
1. At what rate is the flywheel spinning when the power comes back on?
2. How long after the beginning of the power failure would it have taken the flywheel to stop if the power had not come back on?
Express your answer in seconds.
3. How many revolutions would the wheel have made during this time?
In: Physics