# Search results for query: *

1. ### HELP: Equilibrium & Torque

Can someone help me check my work on the other problems, and tell me if they are correct?
2. ### What is the moment of inertia of the ball about the axis of rotation?

can someone please check my work?

What's nil ?
4. ### What is the moment of inertia of the ball about the axis of rotation?

Ok, I redid the problem considering, like you said, the kinetic energy of both linear and rotational movement. so, (0.5)(9.81)(0.81) = (1/2)(0.5)(0.075^2)(w^2) + (1/2)(0.001125)w^2 ---> w=44.68 rad/sec. and velocity when the ball leaves the table is 5.147m/s and d = 2.75meters right?
5. ### What is the moment of inertia of the ball about the axis of rotation?

ok, so b) w = 44.92 rad/sec c) Would the initial velocity of the ball when it leaves the table still be 3.987m/s?
6. ### HELP: Equilibrium & Torque

1) Give the conditions for the equilibrium of an extended object. An extended object is at equilibrium when no force is acting on it. 2) A uniform ladder of length 6.0m and mass 12.0kg is placed against a smooth vertical wall. The ground is rough. a) Calculate the force on the ladder...
7. ### What is the moment of inertia of the ball about the axis of rotation?

A solid sphere of diameter 0.15m and mass 0.5kg is released and rolls without slipping down the ramp. The ramp is 0.81m high and is on a table. The table has a height of 1.40 meters. The balls move freely once it leaves the table. a) What is the moment of inertia of the ball about the axis of...
8. ### HELP:Calculus (area region)

cepheid, I followed what you did and still got -32/3 for #2, but the correct answer is -16/3
9. ### HELP:Volume generated( shell )

HELP:Volume generated("shell") Find the volume generated when the region bounded by the graph of f(x) = 4x^2 and the graph of H(x) = 4 is rotated around the line y = -1 How do I solve this? How do I know if, when rotated, if the solid form a "shell" or a disc, or a washer?
10. ### HELP:Calculus (area region)

1) Find the area of the region bounded by the graphs of f(x) = x^2 - 5x + 3 and H(x) = -x Is H(x) an antiderivative? how do I solve this? 2) Find the area of the region bounded by the graphs of x - y^2 + 2y + 4 = 2 and 2y - 2 - x = 0 so, x = y^2 - 2y - 2 and x = 2y - 2 I...
11. ### X((2x^2) - 2)^3 antiderivative

from there I was suppose to compute as x is goes from 0 to 1 I got 0, but the answer is -1
12. ### X((2x^2) - 2)^3 antiderivative

how do I find to antiderivative of: x((2x^2) - 2)^3
13. ### String wavelength problem

Thanks Andrew Mason!
14. ### Frequency physics homework

It does not give the temperature nor speed of sound.
15. ### Help:Frequency & Speed

Thanks spacetime! :smile:
16. ### Frequency physics homework

A man standing by a rail track, hears the whistle of a train at a frequency of 10419.7 Hertz. The train is moving towards the man at a speed of 39.9 meters/sec. The frequency of the whistle (in Hertz) is Student response 9207.612 Correct answer 9164.147 frequency heard by the man =...
17. ### Help:Frequency & Speed

1) The fundamental of a guitar string whose ends are a distance 0.55m apart has a frequency 283.23 Hertz. If the linear density of the string is 0.01 kG/meter, the tension of the string (in Newtons) is T=f^2 * linear density * wavelength^2 f=283.23 linear density = 0.01 how do find the...
18. ### String wavelength problem

1) A cable made from a metal of density 8850 kG/cubic meter, and whose cross sectional area is 9.6 cubic mm is pulled to a stress of 103.4 Newtons. One end of the string is oscillated with a frequency 480.1 Hertz. The wavelength of the wave on the string (in meters) is T=f^2 * linear mass...
19. ### HELP:Periodic Motion/force

I don't get it either. There must be a way to find the force... :cry:
20. ### HELP:Periodic Motion/force

If the answer is in terms of m than the force is 0.07545M, where M=mass, right? but the correct answer is 976 Newtons.
21. ### HELP:Periodic Motion/force

1) An airplane caught in a storm, is forced into a vertical periodic motion of period 30.2 seconds and amplitude 17.1 meters. The maximum force (in Newtons) acting on a passenger of mass {M} kG is? T=2pi/[sqrt of (max a*gravity)/A)] ---> max a = 0.07545 m/s^2 and F=ma but the mass of the...
22. ### Help:Equilibrium & Angular Momentum

I'm sure the answers that I got were wrong because I worked out other similar problems (same problem but with different numbers) with the same method and still got it wrong.
23. ### HELP:moment of inertia/angular momentum

A solid ball of radius 0.4 meters, made from a material of density 1.7 kG/cubic meter, rolls along a rough horizontal plane with a speed of 11.1 meters/sec. What is its angular momentum (in Joule.secs)? density = mass/volume and volume of a sphere = (4/3)(pi)(r)^3 so the mass is 0.4557kg...
24. ### Help:Equilibrium & Angular Momentum

Is there anyone that can help me with these two problems? :frown:
25. ### Help:Equilibrium & Angular Momentum

1) A plank of mass 2.5 kg and length 2 meters is resting horizontally on two wedges. The first is at one of the ends and the other is a distance 0.3 meters from the second end. If a mass of 0.2 kg is placed on this second edge, what is the force (in Newtons) acting on the second wedge. Here's...
26. ### Help: Derivative: Compute d/dx

Help:Derivative Compute the derivative of d/dx (limit of from -3 to 5x-1) integrand 2[square root of (10 + 5cos(t))]dt
27. ### HELP: Force and Inertia

Okay, I think I get it know. Thanks a BILLION Cyclovenom! :smile:
28. ### HELP: Force and Inertia

Cyclovenom, you said that the center of mass (center of gravity) for an uniform rod is half its length;so, the weight of the plank will act on its center of gravity. That means that the axis of rotation is at the center of mass and r is the distance from the axis of rotation. So, T1 =...

30. ### HELP: Force and Inertia

still getting the wrong answer :frown: T1 = F1(0) T2 = F2(2.3) T3 = -Mg(0.9) T4 = -mg(2.3) (T is torque, M is mass of box, m is mass of plank) sum of T = F1(0) + F2(2.3) - Mg(0.9) - mg(2.3) = 0 F2 = Mg(0.9) + mg(2.3) - F1(0) F2(2.3) = (108.4*9.81*0.9) + (5.6*9.81*2.3) + 0 so, the...
31. ### Questions about simple pendulum

1) A simple pendulum consist of a mass m tied to a string (considered massless) of length L. So would a baseball bat suspended from one end, swinging back and forth, make a simple pendulum? No, right? because the "string" in this case is not massless. Does the string that is swinging the...
32. ### HELP: Force and Inertia

1) Two men are carrying a uniform plank of mass 5.6 kg and length 2.3 meters. A box of mass 108.4 kg is placed a distance 0.9 meters from the first man. Find the force applied by the second man. Here what I did: first man = force 1, second man force 2 F1 + F2 - mg = 0 F1 = (1.4)(5.6)(9.81)...
33. ### HELP:Question about sperm and egg

HELP:Questions about sperm and egg I have some questions I couldn't find the answer to, please help, thanks. 1) What is the importance of the size differences between sperm and an egg? 2) Why is the sperm development complete while still attached to the cytosol? 3) What are the...
34. ### Solving Momentum in Inelastic Collisions

Thanks Leong!
35. ### Solving Momentum in Inelastic Collisions

A bullet of mass 0.11 kg and moving along the horizontal direction with a speed 1129.8 meters/sec hits a wooden block of mass 12.7 kg and gets embedded in it. Find the impulse acting on the block in meters/sec. Here's what I did: initial momentum = (0.11*1129.8) + (12.7*0) = 124.278 final...
36. ### Find Distance from Base to Center of Mass of Ladder

A man of mass 83.8 kg stands on top of a uniform ladder whose mass is 11 kg and whose length is 8.7 meters. Find the distance (in meters) from the base of the ladder to the center of mass. Here's what I did: X(center of mass) = (83.8*8.7) + (11*0) / (83.8+11) = 7.69meters but the...
37. ### ?'s about simple harmonic

Are all periodic motions simple harmonic? Why or why not? What is an example of a periodic motion that is not simple harmonic?
38. ### Angular acceleration/tangential velocity

Can someone please help me on how to solve this problem? Two disks, A and B, are cemented together rotating with angular velocity a . The radius of the small disk B is 2/3 the radius of the larger disk A. a) Calculate the ratio of the tangential velocity of a point on the rim of disk A to...
39. ### Calculus Help: Differentials (Rates)

I keep getting the wrong answer. :confused:

41. ### Calculus Help: Differentials (Rates)

A hemispherical dome with radius 48 feet will be given a coat of paint 0.07 inches thick. Use differentials to estimate the number of gallons of paint that will be needed to paint the dome. Here's what I did: f(x+h) = f '(x)h + f(x) and v=4/3pi*r^3; r=48ft. volume of the dome...
42. ### Calulus Help: Mean Value Theorem

I got the value of c=18 and the question asks to find all numbers c in the interval (2,3). Also, I entered 18 as the answer to this problem and I got it wrong. :confused:
43. ### Calulus Help: Mean Value Theorem

Calculus Help: Mean Value Theorem Let f(x) = x^3 - x on the interval [2,3]. Find all numbers c in the interval (2,3) that satisfy the conclusion of the mean-value theorem. Here's what I did: f '(c) = f(b) - f(a) / (b - a) f '(c) = f(3^3 - 3) - f(2^3 - 2) / (3-2) = 18, but it's...
44. ### Find Min Distance from x=20 to y=3√(x-15)

Find the minimum distance from the point where x = 20 along the x-axis to the curve given by: y= 3 * square root of (x-15) My prof. has not gone over this yet, so can someone help me?
45. ### Help: Force of Resistance

A golfer misjudges a putt, sending the ball a fraction 0.67 of the distance to the hole. If the force of resistance due to the grass is constant, by what fraction should he increase the speed to make the putt? I have no clue how to do this type of problem. Someone please help. Thanks
46. ### Non-ideal collision?

Suppose that a projectile marble and target marble do not collide with their centers of mass equidistant from the floor. What problems in analyzing this experiment are caused by this non-ideal collision? (I could not find anything on non-ideal collision in my textbook.)