Obtain the wavelengths of a photon and an electron that have the same energy of 3.0eV.

A) Find the time tH it takes the projectile to reach its maximum height H.

B) Find tR, the time at which the projectile hits the ground after having traveled through a horizontal distance R.

C) Find H, the maximum height attained by the projectile.

D) Find the total distance R (often called the range) traveled in the x direction; see the figure in the problem introduction.

A 0.280-kg piece of aluminum that has a temperature of -166

A car is moving at 55 miles per hour. The kinetic energy of that car is 5 × 105 J.How much energy does the same car have when it moves at 98 miles per hour? Answer in units of J

12) Two identical particles of charge 6 μC and mass 4 μg are initially at rest and held 4 cm apart. How fast will the particles move when they are allowed to repel and separate to very large (essentially infinite) distance? Answer: Last Answer

Hint: The particles are identical, so you can assume that the scenario is symmetrical. Use energy conservation: What type of energy is stored in the system when the particles are near each other and at rest? How does the voltage of a particle allow you to compute this energy? What about when the particles have flown away from each other? What is the relationship between these energies, according to energy conservation? (Also, remember that the SI unit for mass is the *kilo*gram and you are given the particle masses in *micro*grams.)

Now suppose that the two particles have the same charges from the previous problem, but their masses are different. One particle has mass 4 μg as before, but the other one is heavier, with a mass of 28 μg. Their initial separation is the same as before. How fast are the particles moving when they are very far apart? [Enter the heavier particle's final speed in the first box and the lighter particle's final speed in the second box.]

Answer 1 of 2:

Answer 2 of 2:

Hint: Notice that the asymmetry in the particle masses means that you cannot assume that they end up with the same speeds after separating. Use momentum conservation to help solve this problem.

A uniform stick 1.3 m long with a total mass of 270 g is pivoted at its center. A 3.8-g bullet is shot through the stick midway between the pivot and one end. The bullet approaches at 250 m/s and leaves at 140 m/s. With what angular speed is the stick spinning after the collision?

A 4.0×1010kg asteroid is heading directly toward the center of the earth at a steady 32 km/s. To save the planet, astronauts strap a giant rocket to the asteroid perpendicular to its direction of travel. The rocket generates 5.0×109N of thrust. The rocket is fired when the asteroid is 4.0×106kmaway from earth. You can ignore the earth’s gravitational force on the asteroid and their rotation about the sun.

What is the actual angle of deflection if the rocket fires at full thrust for 300 s before running out of fuel?

A ball of mass m moving with velocity v⃗ i strikes a vertical wall as shown in (Figure 1). The angle between the ball's initial velocity vector and the wall is θi as shown on the diagram, which depicts the situation as seen from above. The duration of the collision between the ball and the wall is Δt, and this collision is completely elastic. Friction is negligible, so the ball does not start spinning. In this idealized collision, the force exerted on the ball by the wall is parallel to the x axis.

Unlike a roller coaster, the seats in a Ferris wheel swivel so that the rider is always seated upright. An 80-ft-diameter Ferris wheel rotates once every 24 s.

What is the apparent weight of a 60 kg passenger at the lowest point of the circle?

What is the apparent weight of a 60 kg passenger at the highest point of the circle?

As a city planner, you receive complaints from local residents about the safety of nearby roads and streets. One complaint concerns a stop sign at the corner of Pine Street and 1st Street. Residents complain that the speed limit in the area (55 mph) is too high to allow vehicles to stop in time. Under normal conditions this is not a problem, but when fog rolls in visibility can reduce to only 155 ft. Since fog is a common occurrence in this region, you decide to investigate. The state highway department states that the effective coefficient of friction between a rolling wheel and asphalt ranges between 0.842 and 0.941, whereas the effective coefficient of friction between a skidding (locked) wheel and asphalt ranges between 0.550 and 0.754. Vehicles of all types travel on the road, from small VW bugs weighing 1370 lb to large trucks weighing 8040 lb. Considering that some drivers will brake properly when slowing down and others will skid to stop, calculate the minimum and maximum braking distance needed to ensure that all vehicles traveling at the posted speed limit can stop before reaching the intersection.

minimum braking distance: ?ft

maximum braking distance: ?ft

Given that the goal is to allow all vehicles to come safely to a stop before reaching the intersection, calculate the maximum desired speed limit. maximum speed limit: ? mph

Which factors affect the soundness of your decision? (can be multiple ones)

Reaction time of the drivers is not taken into account.

Newton's second law does not apply to this situation.

Drivers cannot be expected to obey the posted speed limit.

Precipitation from the fog can lower the coefficients of friction.

What is the effective mass? How is this different from true mass?

Constants

A 3.20 kg box is moving to the right with speed 8.00 m/s on a horizontal, frictionless surface. At t = 0 a horizontal force is applied to the box. The force is directed to the left and has magnitude F(t)=(6.00 N/s2 )t2

What distance does the box move from its position at t=0 before its speed is reduced to zero?

Express your answer with the appropriate units.

If the force continues to be applied, what is the velocity of the box at 3.50 s ?

Express your answer with the appropriate units.

Two-lens systems. In the figure, stick figure O (the object) stands on the common central axis of two thin, symmetric lenses, which are mounted in the boxed regions. Lens 1 is mounted within the boxed region closer to O, which is at object distance p₁. Lens 2 is mounted within the farther boxed region, at distance d. For this problem, p₁ = 10 cm, lens 1 is diverging, d = 16 cm, and lens 2 is converging. The distance between the lens and either focal point is 5.4 cm for lens 1 and 6.9 cm for lens 2. (You need to provide the proper sign).
Find (a) the image distance i₂ for the image produced by lens 2 (the final image produced by the system) and (b) the overall lateral magnification M for the system, including signs. Also, determine whether the final image is (c) real or virtual, (d) inverted from object O or noninverted, and (e) on the same side of lens 2 as object O or on the opposite side.