1- A long jumper leaves the ground at an angle of 17.0
In: Physics
You are in a helicopter towing a 127-kg laser detector that is mapping out the thickness of the Brunt Ice Shelf along the coast of Antarctica. The original cable used to suspend the detector was damaged and replaced by a lighter one with a maximum tension rating of 304 pounds, not much more than the weight of the detector. The replacement cable would work without question in the case that the detector and helicopter were not accelerating. However, some acceleration of the helicopter is inevitable. In order to monitor the tension force on the cable to make sure the maximum is not exceeded (and therefore to not lose the very expensive detector) you calculate the maximum angle the cable can make with the vertical without the cable exceeding the tension limit. (a) Assuming straight and level flight of the helicopter, what is that maximum angle? (b) What is the corresponding acceleration? (c) Your colleague wants to add a 8.00-kg infrared camera to the detector. What is the maximum allowable angle now?
Please make sure to check your work majority of the answers I recieve on here are wrong
In: Physics
A steel ball is dropped from a building's roof and passes a window, taking 0.131 s to fall from the top to the bottom of the window, a distance of 1.12 m. It then falls to a sidewalk and bounces back past the window, moving from bottom to top in 0.131 s. Assume that the upward flight is an exact reverse of the fall. The time spent below the bottom of the window is 1.94 s. How tall is the building?
In: Physics
An empty tin can with height of 30cm and a diameter of 15cm is open at one end and closed at the other end. If the vertical can, with open end down, be slowly immersed in water, how far the water will rise inside the can when the closed end is 10 cm below the water surface?
I know this is easy, but when I'm solving for h, I'm getting a negative value, means that the can will be filled completely?
In: Physics
A sample has a activity of 0.0089 Bq per gram of carbon. (a) Find the age of the sample, assuming that the activity per gram of carbon in a living organism has been constant at a value of 0.23 Bq. (b) Evidence suggests that the value of 0.23 Bq might have been as much as 44% larger. Repeat part (a), taking into account this 44% increase.
In: Physics
In: Physics
The emissivity of the human skin is 97.0 percent. Use 35.0 °C
for the skin temperature and approximate the human body by a
rectangular block with a height of 1.64 m, a width of 35.5 cm and a
length of 25.0 cm.
Calculate the power emitted by the human body.
Tries 0/12 |
What is the wavelength of the peak in the spectral distribution for this temperature?
Tries 0/12 |
Fortunately our environment radiates too. The human body absorbs this radiation with an absorbance of 97.0 percent, so we don't lose our internal energy so quickly. How much power do we absorb when we are in a room where the temperature is 21.0 °C?
Tries 0/12 |
How much energy does our body lose in one second?
Tries 0/12 |
In: Physics
Problem 6.21
A 5000kg truck is parked on a 12? slope.
Part A
How big is the friction force on the truck? The coefficient of static friction between the tires and the road is 0.90.
In: Physics
In: Physics
A 108 m long train starts from rest (at t = 0) and accelerates uniformly. At the same time (at t = 0), a car moving with constant speed in the same direction reaches the back end of the train. At t = 12 s the car reaches the front of the train. However, the train continues to speed up and pulls ahead of the car. At t = 32 s, the car is left behind the train. Determine, the car’s speed the train’s acceleration
In: Physics
In: Physics
In: Physics
In: Physics
42. You are working as an assistant to an air-traffic controller at the local airport, from which small airplanes take off and land. Your job is to make sure that airplanes are not closer to each other than a minimum safe separation distance of 2.00 km. You observe two small aircraft on your radar screen, out over the ocean surface. The first is at altitude 800 m above the surface, horizontal distance 19.2 km, and 25.08 south of west. The second aircraft is at altitude 1 100 m, horizontal distance 17.6 km, and 20.08 south of west. Your supervisor is concerned that the two aircraft are too close together and asks for a separation distance for the two airplanes. (Place the x axis west, the y axis south, and the z axis vertical.)
In: Physics
1. What is the momentum of a photon of light that has a frequency of 2.9 x 10^14 Hz?
a) 1.5 x 10^-28 kg m/s
b) 2.1 x 10^-28 kg m/s
c) 4.4 x 10^-28 kg m/s
d) 6.3 x 10^-28 kg m/s
e) 6.2 x 10^-28 kg m/s
ANSWER E
2. What is the momentum of a photon of light that has a wavelength of 480nm?
a) 1.1 x 10^-27 kg m/s
b) 2.2 x 10^-27 kg m/s
c) 1.8 x 10^-27 kg m/s
d) 1.4 x 10^-27 kg m/s
e) 2.0 x 10^-27 kg m/s
ANSWER: D
In: Physics