Do you know physics?

Question

Two skaters on in-line skates, Lisa and Bart, are initially at rest. They push apart. and start moving in opposite directions. If Lisa's speed just after they push apart is 2.0 m/s and her mass is 85% of Bart's mass, how fast is Bart moving at that time?

Answer 1

Starting from rest, their resultant momentum should be zero at the time of impact.
Considering the magnitudes of momenta,
Lisa's speed X Lisa's mass = Bart's speed X Bart's mass
Thus Bart's speed = 2 X 0.85= 1.7 m/s

This can be done using vectors and velocity also.

Answer 2

its momentum!

mass of lisa x speed of lisa = mass of bart x speed of bart
0.85 x 2 = 0.15 x v
v = 1.7/0.15
v = 11.33 m/s

therefore speed of bart is 11.33 m/s

Answer 3

they each had the same energy of acceleration applied. if E=rate x mass, and it does; and M(L) = .85M(B); then; R(L) x .85M(B) = R(B) x M(B), and; 2m/s x .85M(B) = R(B) x M(B).. so.. dividing by M(B) to isolate rate of bart begats Rate of Bart = 2m/s x .85.. therefore; On a frictionless plane his rate would be about 85% hers or = 1.7 m/s

Answer 4

physics is a lot like that u r now here means because of physics only.think about flight,car,computer or any other equipment today u r utilizing.since physics is the brother of maths & father of electronics,mechanics &.....................a reality for ur dreams comes true by physics. Once put u r all equipment aside & try to live for one day.then u can automatically find answer for u r question.

Answer 5

2.0 m/s

Answer 6

1.7 m/s

Answer 7

1.7 m/s

Answer 8

2.2m/s