Question

Q4.) Calculate the work done by the air drag by solving for Wother in the equation below. Two terms in the equation have a value of zero. You will need the height and mass of the ball and the final velocity.

U1+K1+Wother=U2+K2

height =1.22m

mass=510grams

final velocty =3.667m/s

  Q5.) Calculate the fraction of the initial potential energy this work is (as a percentage), i.e.:

WotherU1×100%

Q6.) What final velocity would you expect in the absence of air resistance? Use the first equation above (for conservation of energy) but leave out Wother.

Q7.) Compare this to the measured final velocity.

Q8.) Do you find the value of lost energy surprising considering your % difference between the measured acceleration due to gravity and the value in the absence of air resistance (9.8m/s2)?

Q9.) The force of air resistance increases with increasing velocity. If the ball fell a shorter distance do you expect the % of energy lost would be more or less?

Answer 1

Ques4

consider the case in which initial velocity is zeros and final potential energy is also zero, So, K1 = U2 =0

Ques 5, fraction of initial potential energy,

f =

f=

f = 56.2 %

Ques 6

final velocity when Wother = 0

Ques 7

So measured final velocity is =3.667 m/s

and v_f = 4.89 m/s

So,

error =

         = 33.35 %

Ques 8

Final KE without air drag,

                                       

                                        

final KE with air drag,

                                   

percentage difference =

                                     = 28 %