were solving for v velocity of the ball after it has hit the bottle. a. momentum ->p=mv->ball + bottle momentum during hit = ball + bottle momentum after hit-> ball (.5*21)+ bottle (.2*0) (it's 0 because the the bottle is standing still) = ball after hit (.5*v)+bottle after hit (.2*30) -> 10.5+0=.5v+6 ->4.5=.5v->v=9m/s

b. if bottle was heavier the ball would be slower so final velocity would decrease

8 0

2 years ago

A person applies a force of 67 N for a distance of 11 m to push a desk across the floor. How much work is done

lbvjy [14]

L=F*d=67*11=737 Joule

7 0

2 years ago

a train moving west with an initial velocity of 20m/s accelerates 4m/s2 for 10 seconds . during this time , the train moves a di

Blababa [14]

X=1/2at^2+vt+x0
x=1/2(4)(100)+20(10) = 400 m

8 0

3 years ago

Particle A and particle B are held together with a compressed spring between them. When they are released, the spring pushes the

Genrish500 [490]

Explanation:

Given:

Final speed of mass A = Va

Final speed of mass B = Vb

Mass of A = Ma

Mass of B = Mb

Ma = 2 × Mb

By conservation of linear momentum,

0 = Ma × Va + Mb × Vb

0 = 2 × Mb × Va + Mb × Vb

Vb = - 2 × Va

Energy of the spring, U = 1/2 × k × x^2

1/2 k x² = 1/2 × Ma × Va² + 1/2 × Mb × Vb²

35 = 1/2 × Ma × Va² + 1/2 × Mb × Vb²

Ma × Va² + Mb × Vb² = 70

2 × Mb (-Vb/2)² + Mb × Vb² = 70

1/2 × Mb × Vb² + Mb × Vb² = 70

3/2 × Mb × Vb² = 70

Mb × Vb² = 140/3

= 46.7 J

Ma = 2 × Mb and Vb = - 2 × Va

Ma/2 × (4 × Va²) = 140/3

Ma × Va² = 70/3

Kinetic energy of mass A, KEa = 1/2 × Ma × Va² = 23.3 J

Kinetic energy of mass B = 1/2 × Mb × Vb² = 46.7 J

8 0

2 years ago