A hair dryer has two settings: 840 W and 1320 W.
(a) At which setting do you expect the resistance to be higher?
840 W correct
After making a guess, determine the resistance at each setting.
(b) 840 W setting
(c) 1320 W setting
Homework Equations
I am not exactly sure what...
A 50 dB sound wave strikes an eardrum whose area is 4.1 * 10-5 m2.
(a) How much energy is absorbed by the eardrum per second?
W
(b) At this rate, how long would it take your eardrum to receive a total energy of 1.0 J?
years
I have tried to solve using I=2pi^2f^2A^2pv
and got f=280 ...
I have tried this problem many times using different equations and none of them have worked how do I solve this?
A cord of mass 0.51 kg is stretched between two supports 26 m apart. If the tension in the cord is 148 N, how long will it take a pulse to travel from one support to the other?
Studying for exams need help very soon!
On both of these I got the right answer but it was so long ago I have no idea how to do them.
(Which equation am I to use?)(v=Vo+at? if so how?)
1.Determine the stopping distances for an automobile with an initial speed of 91 km/h and human reaction...
6. A car is driven 140 km west and then 30 km southwest. What is the displacement of the car from the point of origin (magnitude and direction)?
? km ( I know that this one is 162.5)
?° south of west ( I have no idea how to find this answer)
:bugeye:
A 6520 kg helicopter accelerates upward at 0.57 m/s2 while lifting a 1190 kg car.
(a) What is the lift force exerted by the air on the rotors?
_________ N
(b) What is the tension in the cable (ignore its mass) that connects the car to the helicopter?
_____N
I have no idea how to do...
I am not sure how I am supposed to do these problems and I am going to be tested on them soon can someone please help me.
1) An 83 g arrow is fired from a bow whose string exerts an average force of 95 N on the arrow over a distance of 85 cm. What is the speed of the arrow as it leaves the...
A passenger on a boat moving at 1.13 m/s on a still lake walks up a flight of stairs at a speed of 0.50 m/s, Fig. 3-44. The stairs are angled at 45° pointing in the direction of motion as shown. What is the velocity of the passenger relative to the water? :cry:
I have to get the magnitude of...
A swimmer is capable of swimming 1.15 m/s in still water.
(a) If she aims her body directly across a 150 m wide river whose current is 0.80 m/s, how far downstream (from a point opposite her starting point) will she land?
:cry: I have tried this twice and I have gotten the wrong answer does...
During a rodeo, a clown runs 8.0 m north, turns 35 degrees east of north, and runs 3.5 m. Then, after waiting for the bull to come near, the clown turns due east and runs 5.0 m to exit the arena. What is the magnitude of the clown's total displacement?
When I did this I got a trapazoid...
A football player runs directly down the field for 35 m before turning to the right at an angle of 25 degrees from his original direction and running an additional 15 m before getting tackled. What is the magnitude of the runner's total displacement?
I got 38.08 but it is not right can...