Recent content by disque

yea i got it, i had a negative sign and it was positive. not really sure why but thanks for your help

Homework Statement Three point charges Q1 = 2.9 mu or micro C, Q2 = 4.9 mu or micro C and Q3 = 3.9 mu or micro C, are arranged as shown. Homework Equations PE=k(q1q2/r+q1q3/r+q2q3/r) k=8.99e9 The Attempt at a Solution By using that equation I plugged in the lengths and changed...

221 PU by any chance? if so do u know how to work the first question with the 2 charges and then one being placed on the origin making it zero. It wants us to find the distance from from the origin to the charge on the right. hopefully that makes sense thanks

Homework Statement A small drop of water measuring 0.6 mm in diameter, hangs suspended above the ground due to the Electric field of the Earth (140 N/C). How many extra electrons are on the drop of water? Homework Equations i know k=8.99 x 10^9 abs(f)=K((q)/(r^2)) The Attempt at a...

h = 90/(pir^2) derivative of SA = 2pi*pir^2*r^2+90pi, denominator not needed, setting equal to zero.

Homework Statement A cone-shaped paper drinking cup is to be made to hold 30 cm3 of water. Find the height and radius of the cup that will use the smallest amount of paper. Homework Equations volume of a cone (1/3)(pi)(r^2)(h) = 30 SA of a cone pi(r)[sqrt(r^2 + h^2)] The Attempt at...

Homework Statement Imagine a frictionless pulley (a solid cylinder) of unknown mass M and radius r = 0.200 m which is used to draw water from a well. A bucket of mass m = 1.50 kg is attached to a massless cord wrapped around the pulley. The bucket starts from rest at the top of the well and...

I know the center of mass of the 2 is in the radius of the sun because the suns size compared to earth, but i don't know the first part still?

Well, center of mass equation is (m_1r_1+m_2r_2)/(sigma)m_1)

I got it (lmg)/2 :)

Homework Statement A baseball player holds a bat at the end of the handle. If the bat is held horizontally, what is the approximate torque due to the force of gravity on the bat, with a pivot point at the batter's hands? Assume that the the bat is uniform. Use L for length of the bat, m for...

Homework Statement Consider the Sun and the Earth as a 'system' of two 'particles'. The center of mass of this system lies a distance L from the center of the Sun. Find L and compare it to the radius of the Sun. The center of mass of the Earth-Sun system lies? A. inside the radius of the...

Homework Statement Bobsled A bobsled run leads down a hill as sketched in the figure above. Between points A and D, friction is negligible. Between points D and E at the end of the run, the coefficient of kinetic friction is µk = 0.4. The mass of the bobsled with drivers is 210 kg and it...

Alright thanks a lot that makes sense! :)

Homework Statement Josie and Charlotte push a 12-kg bag of playground sand for a sandbox on a frictionless, horizontal, wet polyvinyl surface with a constant, horizontal force for a distance of 6 m, starting from rest. If the final speed of the sand bag is 0.5 m/s, what is the magnitude of...