1. If transverse waves on a string travel with a velocity of 20 m/s when the str
ID: 1315006 • Letter: 1
Question
1. If transverse waves on a string travel with a velocity of 20 m/s when the string is under a tension of 30 N, what tension will be required for the waves to travel with a velocity of 40 m/s on the same string?
2. A 1200 kg car is moving at 5.0 m/s EAST. It strikes an 1800 kg car at rest. The cars have an elastic collision and move in the EAST or WEST direction. The relative velocity between the cars after the collision is?
3. Seven liters of a fluid with a specific heat of 2.93 kJ/(kg x K) or 0.700cal/(g x K) at 20C is mixed with three liters of the same fluid at 32C. Suppose that the fluid is insulated so that no energy can flow into it or out of it. What is the final temperature of the fluid? You do not know the density of the fluid, but you do know that the density is constant over this temperature range.
Thank you!!
Explanation / Answer
1.V is proportional to sqrt(T)
V2/V1 =sqrt(T2/T1)
T2=(V2/V1)^2 *T1=(40/20)^2 *30 =120N
2. momentum conservation
1200*5=1200*v1 + 1800*v2
2v1+3v2=10
0.5*1200*5^2 =0.5*1200*v1^2 +0.5*1800*v2^2
2v1^2 +3v2^2 =50
putting v2 =(10-2v1)/3
2v1^(2) +(10-2v1)^2/3 =50
v1=-1 and v2=4
relative velocity =v2-v1=5m/s
3.
rho*7*2.93*293 + rho*3*2.93*305=rho*10*2.93*T
T=296.6K=23.6 degree celsius
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.