Hello Yomama
This can be done very quickly and effectivelly with the assistance of two energy equations:
Potential energy=mgh
Kinetinc Energy=(mv^2)/2
Equate the two in the following way:
mgh=(mv^2)/2 Note: m cancelles out...
Plug in the minut(-) before the 3. Remember that the car is moving the other way, so it has to stop and start moving in the opposite direction before it can catch up with the other one(velocity wise.)
Try:
6.3=-3+2.9(t)
Find t.
Hubert
Question A-elevator)
Forces pointing downwards: Weight of lift
Forces pointing upwards: Tension force, ma(where m and a are mass and acceleration of lift respectivelly)
Balance the two equations to find the missing link: The tension force.
QuestionB-ice skater)
Do exactly...
Redd is absolutelly right:
The law of conservation of momentym states that:
Initial Momentum=Final Momentum
if M=mass of bowl and m=mass of pin, V=velovity of bowl and v=final velocity of pin then:
MV=mv+Mx where: x=final velovity of bowl...
A) Find the first time and height of the ball after the projection upwards:
compare energies to find height:
mgh=mv^2/2 where: m cancelles out, v=15 and g =9.81, find h(height)
Alternativelly:
Find time for the ball to stop from...
A very tough question I'm trying to solve from my textbook as revision before exams.
Thanks in advance.
http://img509.imageshack.us/img509/1398/assignment.jpg