Recent content by kirby27

can anyone else also confirm this answer?

A student is sitting on a frictionless rotating stool with her arms outstretched holding equal heavy weights in each hand. If she suddenly let's go of the weights, her angular speed will: A) increase B) stay the same C) decrease attempt: i think it's B because angular speed is V/r and...

Two unequal masses m and 2m are attached to a thin bar of negligible mass that rotates about an axis perpendicular to the bar. When m is a distance 2d from the axis and 2m is a distance d from the axis, the moment of inertia of this combination is I. If the masses are now interchanged, the...

ok. i think its V/2?

Two points are on a disk that rotates about an axis perpendicular to the plane of the disk at its center. Point B is 2.00 times as far from the axis as point A. If the linear speed of point is V, then the linear speed of point A is I know the speed of A must be less and i think its V/4. Is...

Two identical merry-go-rounds are rotating at the same speed. One is crowded with riding children; the other is nearly empty. If both merry-go-rounds cut off their motors at the same time and coast to a stop, slowed only by friction (which you can assume is the same for both merry-go-rounds)...

you said it is 5.11 N. isn't it 5.11E-8 N?

calculations: D acting on A: F=(6.673E-11)[4/.1414^2]. i got the .1414 from pythagorean using .1 as a and b. F=1.3346E-8 B acting on A: F=(6.673E-11)[4/.1^2] F=2.669E-8 --> but this is not downward pull using SOH CAH TOA i did cos(45)=x/2.669E-8 x=1.89E-8 --> this needs to be multiplied by...

i re-did it and got 6.67E-8 is this correct?

before i write it all out is this the right method?

Each mass in the figure below is 2.00. Find the magnitude of the net gravitational force on mass A due to the other masses in figure b (the square). Figure: http://i.imgur.com/fjSgU.jpg attempt: i used the formula F=G [(m1*m2)/r^2]. all of the forces are in the direction of D so i...

The 4.00kg block in the figure is attached to a vertical rod by means of two strings. when the system rotates about the axis of the rod, the strings are extended and the tension in the upper string is 80N. A: What is the tension in the lower cord? B: what is the speed of the block? FIGURE...

the second part of the questions asks "Find the force the balls exert on each other." i think the only force they have on each other is the x component of tension. so I am guessing the answer is 78.6cos(65)=33.2. but the problem gives the diameter of the balls and i haven't used that number...

thank you very much

ok i think i got it. is it 71.2/cos(25) = 78.56?