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.

1. Consider a gas of molecules in thermal equilibrium with temperature T and a number n per area, confined to a 2-D flat surface.

-What is the kinetic energy per area of the gas?

-What is the force per length that these molecules exert on an edge of the surface?

-If there are diatomic molecules, what is the rotational energy per area of the gas? (Assume that each atom of each molecules is confined to a flat surface)

Can someone explain to me Bohr's model of hydrogen and Bohr Selection Rule

An object with m₁ = 5kg is attached to a spring of negligible mass. This mass/spring combination is then slid horizontally on a frictionless surface with a velocity of 5m/s towards a stationary object with m₂ = 6kg. Upon impact, the spring compresses, then we examine two cases. First, find the velocities of the two objects assuming the spring completely relaxes again after the interaction. Second, assume that m₂, after they separate, slides up a frictionless incline.

(a) What is the relative speed of the masses when the spring is maximally compressed?

(b) When the spring is completely compressed, how much potential energy does it have?

(c) If the spring constant is k = 2000 N/m, by how much (what distance) is the spring compressed at that point?

(d) If the spring relaxes while still on at ground, what is the kinetic energy of m₂ just before it slides up the hill?

(e) If there is no friction on the hill, how high up the hill does m₂ go?

(f) If there is friction on the hill, and m₂ goes up the hill to a height of 0.5 meters, how much energy was dissipated?

An 18-kg sled starts up a 36 ∘ incline with a speed of 2.2 m/s . The coefficient of kinetic friction is μk= 0.25.

How far up the incline does the sled travel?

What condition must you put on the coefficient of static friction if the sled is not to get stuck at the point determined in Part A?

If the sled slides back down, what is its speed when it returns to its starting point?

How did the Conservation of Momentum allow Chadwick to prove the existence of the neutron when it was believed that the combination of protons and electrons alone made atoms?

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Question: This is my second time posting this:   Question: I have been working on this and I have...

This is my second time posting this:  

Question: I have been working on this and I have done it. But I am not sure what velocity versus time plot,...

I have been working on this and I have done it. But I am not sure what velocity versus time plot, acceleration versus time plot, position versus time plot. I just want to make sure I am doing it the right way. Please be sure to do it the right way and provide a correct answer.  

Go to   http://phet.colorado.edu/en/simulation/moving-man and download the simulation saving as a file. Click on moving-man_en.jar in the download window. Accept the agreement and begin the simulation.   You will do that for all the experiments in the class. Do not delete the given content in the assignment. Highlight your answers using yellow color

When the simulation begins, click on the Charts tab. Click on the bottom negative magnifying glass (lower right corner) until the time scale reads 20 sec. Similarly, set the acceleration a maximum scale of 4.7 m/s². Then set the maximum velocity scale to 5.8 m/s. Leave the maximum position at ±10 m.

In all of the following simulations, when one of the graphs is about to go outside the given scale, Pausethe simulation.

Set position = -10.0 m, velocity = 0.0 m/s, and acceleration = 0.10 m/s² by typing the value in the corresponding box.   Clear the simulation and then Play the simulation, pausing when the position reaches the scale limit of 10 m.

[Type your answer here]

(a) Describe the position versus time plot.

b) Describe the velocity versus time plot.

[Type your answer here]

c) Describe the acceleration versus time plot.

[Type your answer here]

2. Set the position = 10.0 m, the velocity = -4.0 m/s, and the acceleration = 0.45 m/s²

Click Clear at the bottom and then Play. Pause the simulation when the position is just about to exceed 10m.

a) Describe the position versus time plot.

[Type your answer here]

b) Describe the velocity versus time plot.

[Type your answer here]

c) Describe the acceleration versus time plot.

[Type your answer here]

An air-track cart with mass m1=0.28kg and initial speed v0=0.80m/s collides with and sticks to a second cart that is at rest initially.

Part A

If the mass of the second cart is m2=0.53kg, how much kinetic energy is lost as a result of the collision?

Express your answer to two significant figures and include appropriate units.

What is the difference in finding magnitude of a force on a charge and finding the net electric force acting on a charge?

If given three charges set at a certain places set on a triangle, how would you find the magnitude of a force on one of the charges? Please create a simple example and show each step clearly and explanation for what to do in each step esecially on how to find, set up, and use the components to add the forces together and determine the vector sum of forces.

If given four charges set at a certain places set on a square, how would you find the magnitude of a force on one of the charges? Please create a simple example and show each step clearly and explanation for what to do in each step esecially on how to find, set up, and use the components to add the forces together and determine the vector sum of forces.

If an electron is moving at a certain speed and at a certain angle to a magnetic field, how do I find the force of that electron? Please give me the equation and the rearranged eqation for finding the answer. Please tell me what each letter of the equation stands for and their units. Please create a simple example and take me step by step on how to solve and include the final units of the answer.