107k views
1 vote
At t=0, an 830-g mass at rest on the end of a horizontal spring (k = 169 N/m ) is struck by a hammer which gives it an initial speed of 2.32 m/s.

Determine (a) the period and frequency of the motion, (b) the amplitude, (c) the maximum acceleration, (d) the total energy, and (e) the kinetic energy when
x =0.40 A, where A is the amplitude.

User Lauren Yim
by
4.4k points

1 Answer

5 votes

Answer:a) T=0.44seconds and f=2.29Hz

b) A=0.1626m

c) amax=33.11m/s^2

d) E=2.2337J

e) KE=1.8732J

Step-by-step explanation:

Period of the motion :

T=2π√m/k

T=period,m=mass of the body, k=spring constant

Converting mass from gram to kilogram :

M=830g/1000=0.83kg

T=2π√0.83/169=0.44038seconds

T=0.44secs(approximately)

Frequency of the motion :

F=1/T

Where T=0.44038seconds

F=1/0.44038s=2.27Hz

b) maximum speed :

Vmax=A√k/m

Where A=amplitude,m=mass of the body, k=the spring constant

Making A the subject of the formula:

A=Vmax√m/k

Where, speed(V)=2.32m/s as Vmax and 0.83kg for m and 169N/m for k.

A=(2.32m/s)√(0.83kg)/(169N/m)= 0.1626m

c) Maximum acceleration :

amax =A(k/m)

Therefore, A=

(0.1626m)(169N/m)/0.83kg)

A=33.11m/s^2

d) Total Energy :

E=1/2MVmax

Where, M=0.83kg and Vmax=2.32m/s

E=1/2*(0.83kg)*(2.32m/s)^2

E=2.2337J

e) From the law of conservation of mass :

1/2kA^2=1/2Kx^2+KE

Where x=0.04A

KE=1/2kA^2-1/2kx^2

KE=1/2kA^2(1-0.4^2)

KE=Etotal*0.84

Where, Etotal=2.23J

KE=2.23*0.84=1.8732J

User Arunvg
by
4.6k points