# Search results

• Users: bard
• In Introductory Physics Homework Help
• Order by date
1. ### Peicewise limit help

ok so lim(x->1+)=(1+1)=2 lim(x->1-)=(1+1)=2 so the limit exists, i don't understand how that helps in finding the overall limit of F(x) at 1.
2. ### Peicewise limit help

sorry that should be x+1
3. ### Peicewise limit help

F(x)= 2x^2, x<1 3, X=1 X+, x>1 Find lim(x-->1) f(X) f(1)= not exactly sure how to do this. would not f(1) be just 3, since it is defined as that in the function. I am not sure about how to take that limit. Thanks
4. ### Limit lim(x->pi/4) tan(2x) =tan(pi/2)

lim(x->pi/4) tan(2x) =tan(pi/2) wat to do after this, it is undefined

what is the difference between amino acids on their own and amino acids that have been incorporated into a polypeptide chain? My answer is that amino acids on their on do nothing. However when they interact they create a protein which eventually takes on a particular function. why does...
6. ### Help-physics to get started

Hi Doc Al, Almost solved it the a i use here will be angular acceleration so net torque=T*R or Ia=T*R Ia=(mg-mRa)R Ia=mgr-mR^2a Ia+mgR^2a=mgr a(Ia+mR^2)=mgr a=mgr/I+mR^2 for acceleration the tension is a=mR^2g/(I+mr^2)
7. ### Help-physics to get started

An object of mass m is tied to a light string wound around a wheel that has a moment of inertia I and radius R. The wheel bearing is frictionless and the string does not slip. find the tension and the acceleration of the object. I think mg-T=ma and that I=MR^2 thats all i know can...
8. ### Help-santa claus problem

ok i understand. What i don't understand is how to write a "physics story". I guess that i have to describe what's going on in the problem?
9. ### Help-santa claus problem

Chubby Santa(mass 100kg) decides to have some fun and slides 9.0 m down a snowy roof)starting from rest. There is a 135 n fricitional force between santa and the roof. After sliding the 9.0 meters he collides with and clings to, an elf (mass 50kg) who was sitting on the roof edge. They both fall...
10. ### Check answer for momentum prob

yah i got the answer as -.57m/s. thnx
11. ### Check answer for momentum prob

then i would get a negative v since v'=325-450/40=-3.125m/s
12. ### Check answer for momentum prob

so the m_{2}v_{2) becomes negative? i don't understand what u mean by "direction matters"
13. ### Check answer for momentum prob

A 130-KG tackler moving at 2.5 m/s meets head on(and tackles) a 90 k-g halfback moving at 5.0 m/s. What will be their mutual speed immediatley after the collison? someone please check my work m_{1}v_{1}+m_{2}v_{2}=v'(m_{1}+m_{2}) so v'=\frac{325+450}{220} v'=3.52 m/s
14. ### Billiard ball Momentum help

Hey Doc Al, thnx for helping me through this process :). I got \theta_{2}=-33 v'_{B}=.81 m/s
15. ### Billiard ball Momentum help

yes i plugged in numbers and i got .068=v'_{B}\cos\theta'_{2 -.72=v'_{B}\sin\theta'_{2} thats all i can do to simplify
16. ### Billiard ball Momentum help

can someone help me in simplifying these equations? thnx
17. ### Billiard ball Momentum help

well I am not sure whether this problem has a definite answer(as in 1.2 or 3.4 etc)or whther I am suposed to solve in terms of variables
18. ### Billiard ball Momentum help

A billiard ball of mass m_{A}=0.400kg moving with a speed v_{A} =1.8m/s strikes a second ball, initially at rest, of mass M_{B}=0.500kg. As a result of the collision, the first ball is deflected off at an angle of 30\deg with a speed of v'_{A}=1.1 m/s. a) taking the x-axis as the positive...

So the kinetic energy would be 1/2*184(0.052)^2=.25J

so the total energy would be 1/2 KA^2
21. ### Problem of Springs

thnx a lot man
22. ### Problem of Springs

yes but i get v=0 when i do the derivative. is this correct? thnx for ur help
23. ### Problem of Springs

ok so i have to take the derivative x=3.0\cos(5\pi t+\pi) so the derivative of that would be 3.0*-\sin(5\pi(0.5)+\pi)*d/dx(5\pi(0.5)+\pi
24. ### Problem of Springs

yes i need to calculuate velocity, but i don't know how to get it.
25. ### Problem of Springs

I have no idea what you are talking about? are my other answers correct?
26. ### Problem of Springs

A particle has displacement given byx=3.0\cos(5\pi t+\pi) where x is in meters and t in seconds A)What are the frequency ,F, and the period,T, of motion B)What is the greatest distance the particle travels from equlibrium c)Where is the particle at time t=0?t=0.5(s) D)What is the velocity...

At t=0, a 650-g(0.65kg) mass at rest on the end of a horizontal spring(k=184n/m) is struck by a hammer which gives it an initial speed of 2.26 m/s. Determine (a) the period and frequency of the motion (b)the amplitude (c)the maximum acceleration (d) the position as a function of time (e) the...
28. ### Integration help

hey everyone i need help with this antiderivative \int\sec^{2}x\tan^{4}x my guess is that it is tan^5(x)/5
29. ### Spring mass help-desperate

ok i got v=1.59 for part A and v=1.18 for part b how do i find the total energy of the system?
30. ### Spring mass help-desperate

ok i found K as 1.27 and plugged it back so \ so i got the velocity as 0.28m/s is this right so then the velocity from 0.1 m from equibium would be .78m/s c) total energy of the system would be 1/2KA^2=0.014--dosent make sense thnx
31. ### Spring mass help-desperate

spring mass help--desperate A 0.35-kg mass at the end of the vibrates 3 times per second with an amplitude of 0.15m. Determine (a)the velocity when it passes the equilibrum point (b)the velocity when it is 0.10m from the equilibrum point(c)the total energy of the system(d)the equation...