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# Peg

Questions11
• ### Physics help?

An astronomer looking at a star's spectrograph sees a bright line at 29.2x106 MHz. What is the wavelength of the electromagnetic radiation creating the bright line in nanometers?

The radio station WFIG broadcasts 95.4 MHz. What is the wavelength of the radio waves. (HINT: You will need to convert MHz! )

• ### Help with physics homework please?

An astronomer looks at a comet which is 9.30 x 109 km away. How many minutes did it take the light from the comet to reach the astronomer? (HINT: you will need to change kilometers to meters and seconds to minutes)

6 AnswersAstronomy & Space4 months ago
• ### Help with physics homework?

NASA communicates with their space probes using radio waves. How many kilometers away is a space probe if it takes 745 seconds for the signal from Earth to reach the probe? (HINT: solve for distance in meters first!)

4 AnswersAstronomy & Space4 months ago
• ### homework help?

A box of mass 18.8 kg starts at rest and is pulled by a force of 128 N applied at an angle of 35.0º to the horizontal. There is no friction.

The box is pulled a distance of 18.2 meters.

What is the the acceleration of the box?

• ### homework help?

A box of mass 18.8 kg starts at rest and is pulled by a force of 128 N applied at an angle of 35.0º to the horizontal. There is no friction.

The box is pulled a distance of 18.2 meters.

What is WORK is done on the box?

• ### Homework help?

A box of mass 11.1 kg starts at rest and is pulled by a force of 20.0 N applied at an angle of 35.0º to the horizontal.

After being pulled a distance of 4.42 meters the velocity of the box is 1.75 m/s.

Use the work-energy theorem to find the net work done on the box.

.

• ### Help with homework?

A cat runs straight off a table and pounces on a mouse, as shown in Diagram-7. The height of the table is 0.51 m and the cat leaves the table traveling at 4.0 m/s.

How long (s) is the cat in the air?

• ### Help with homework?

A cannon fires a shell with a muzzle velocity of 64.2 m/s. The cannon is fired at an angle of 40.6 degrees to the ground. How high will the shell go ? Neglect air resistance.

• ### Help with homework?

An alien invasion begins! Kodos lands on a hill that is 12.1 meters above the floor of the valley. Fortunately you are ready with a cannon on top of a cliff that is 26.3 meters above the floor of the valley.

How fast should you fire the cannon ball to strike Kodos and save the Earth if Kodos is 18.9 meters away measured horizontally from the cliff face? (HINT! What is ∆y?)

• ### Homework Help?

Kanga and Roo slide down an muddy frictionless incline which takes them 6.0 seconds. The acceleration down the incline is 4.0 m/s2 . Make a table of motion variables

a) How long is the incline?

b) How fast are Kanga and Roo moving at the bottom of the incline?

• ### Homework Help?

A driver brings a car traveling at 22.0 m/s to a full stop in 2.00 s. Assume the acceleration is constant.

a) List what you know at the start of the problem below. If a variable is not known, use "?". Down is negative (-)

Δx =

vi =

vf =

a =

Δt =

b) What is the acceleration of the car?

c) How far does the car travel before stopping?

Physics11 months ago
• ### Homework Help?

An arrow is fired into the air with an initial speed of 35.6 m/s. How high is the arrow after 5.23 seconds?

a) List what you know at the start of the problem below. If a variable is not known, use "?". Down is negative (-)

Δx =

m

vi =

vf =

a =

Δt =

b) How high is the arrow after 5.23 s?

c) What is the velocity of the arrow at it's highest point?

m/s

d) How high is the arrow at its highest point?

e) How long is the arrow in the air for the COMPLETE flight?

• ### Homework Help?

A person wearing a shoulder harness seat belt can survive a car crash if the acceleration is no more than -300.0 m/s2.

The car crashes while traveling at 17.6 m/s

Assuming a constant acceleration, how far must the front end of car collapse?