Calculate the heat that must be supplied to a 500g copper kettle containig 750 g of water to raise its temperature from 23 degrees to the boiling point of water, 100 degrees.
q=MCT
qwater= 750 x 4.184 x 77= 241626 J
qcopper= 550 x .38 x 77= 16093 J
241626 + 16093 =...
The question only asks for one speed, and I added the 97 and subtracted 97 and it was still wrong. And its when you are moving away from the parked car, so wouldn't it be subtracted, anyway? And you're solving for the velocity when you're moving away.
So all in all, I have no idea what you...
The security alarm on a parked car goes off and produces a frequency of 952 Hz. The speed of sound is 343 m/s. As you drive toward this parked car, pass it, and drive away, you observe the frequency to change by 97 Hz. At what speed are you driving?
F=Fo [(Vsound-...
A 2.40 kg object is hanging from the end of a vertical spring. The spring constant is 40.0 N/m. The object is pulled 0.200 m downward and released from rest. Complete the table below by calculating the translational kinetic energy, the gravitational potential energy, the elastic potential...
The base of an isosceles triange has length b and the two sides of equal length each measure 30 cm. Find the area A of the triangle as a function of b.
a squared + b squared = c squared
Area= .5bh
.5b squared + h squared = 30 squared
h= (-.5b squared + 900) ^ 1/2
Area= .5 x b x...
A bodybuilder is holding a 20-kg steel barbell above her head. How much force would she have to exert if the barbell were lifted underwater?Fb= Density x Volume x Gravity
Density= mass/volume
7860= 20/ V
V= .00254 m^3
Fb= 1000 x .00245 x 9.81
Fb= 24.9174 N
An irregularly shaped chunk of concrete has a hollow spherical cavity inside. The mass of the chunk is 34 kg, and the volume enclosed by the outside surface of the chunk is 0.035 m3. What is the radius of the spherical cavity?
D=m/v
4/3 pi r^3= volume of a sphere
2200 kg/ m cubed...
The main water line enters a house on the first floor. The line has a gauge pressure of 2.00 x10^5 Pa.
(a) A faucet on the second floor, 7.0 m above the first floor, is turned off. What is the gauge pressure at this faucet?
P2= P1 + (density x g x h)
(2 x 10^5)= P1 + (1000 x...
Suppose you are riding a stationary exercise bicycle, and the electronic meter indicates that the wheel is rotating at 8.4 rad/s. The wheel has a radius of 0.40 m. If you ride the bike for 2090 s, how far would you have gone if the bike could move?
w= rad/ sec
2 pi= rev
v= m/s
2pi x r=...
Batman (mass = 105 kg) jumps straight down from a bridge into a boat (mass = 530 kg) in which a criminal is fleeing. The velocity of the boat is initially +15 m/s. What is the velocity of the boat after Batman lands in it?
.5mv squared + mghf = .5mVi squared + Mghi.5 x 635 x Vf squared = .5 x...
When chasing a hare along a flat stretch of land, a greyhound leaps into the air at a speed of 9.9 m/s, at an angle 27 degrees above the horizontal
Vf= Viy + at
displacement= Vyt + .5at squared
0= 4.95 (y component for velocity) + 9.81t
t= .504
y= 4.95x.504 + .5x9.81x.504 squared
y...
A ball is thrown upward from the top of a 24.2-m-tall building. The ball's initial speed is 12 m/s. At the same instant, a person is running on the ground at a distance of 29.2 m from the building. What must be the average speed of the person if he is to catch the ball at the bottom of the...