If a racket strikes a ball (m = 100 g) with a force of 2000 n for 0.3 s., calculate the velocity the ball has as it leaves the racket, assuming it starts from rest.
v = m/s

6 m/s
60 m/s
600 m/s
6000 m/s

By impulse definition we have to:

F * Δt = m * Δv

Where,

F: Applied force

Δt: change in time

m: mass

Δv: change in speed

Substituting values we have:

2000 * (0.3 - 0) = (0.1) * (v - 0)

From here, we clear the speed.

We have then:

2000 * 0.3 = 0.1v

v = (2000 * 0.3) / (0.1)

v = 6000 m / s

the velocity the ball has as it leaves the racket, assuming it starts from rest is:

v = 6000 m / s

  1.the balanced   chemical equation is as below

cu +   2 ag(no)₃ → cu(no₃)₂   +2 ag

2.the   much silver   produced   is   50.9 g

step 1: find the   moles of cu

moles =   mass÷   molar mass

  from periodic table the molar mass of cu = 63.5 g/mol

moles is therefore = 15.00 g÷ 63.5 g/mol = 0.236   moles

step 2: use the mole ratio to determine the   moles of ag

from equation above   cu: ag   is 1: 2

therefore the moles of ag   =0.236   moles   x 2/1 =0.472   moles

step 3: find the mass   of ag

mass = moles x molar mass

from periodic table   the molar mass of ag =107.87 g/mol

mass   = 0.472   moles x 107.87 g/mol = 50.9 g

3.   the   much   silver   collected worth is   1.797 oz

  convert   50.9 g   to oz

that is   1 gram = 0.0353 oz

          50.9 grams =?   oz

by cross multiplication

={(50.9 grams x 0.0353 oz) / 1   gram}   =1.797 oz

he made 11 calls in one day