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TQGuru
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Hi guys I am looking for help with some formulas, its for hnc mech eng, the question is as follows a winding drum with moment of inertia 24 kg m2 and a winding radius of 0.6m is used to accelerate a loaded hoist with mass of 850kg at a rate of 0.8ms by means of a cable, frictional resistance can be considered as a torque of 88 Nm
determine
1- the tension required in the cable
2- angular acceleration in rads/sec
3- Accelerating torque in Nm at the winding drum shaft required to accelerate the system
4- The total driving torque in Nm required at the winding drum shaft to produce the required motion of the whole system
I got 1 as 90,185N
2 - 1.33 rads/s
3- 5411Nm
4 is 5531Nm but I am not sure how to derive at this answer
The question then goes on to velocity time diagram like questions and asking for sketches
the hoist covers a distance of 20m accelerating at 0.8ms from rest to a max speed then decelerates at the same rate, i.e for 10m constant acceleration
the part of the question I am struggling with is where it asks for the maximum velocity of the hoist, this is 4ms but I am beat for knowing the calculation as I don't have an specific time, Could anyone help me with the formula required to achieve the answer of 4ms?
Many thanks!
determine
1- the tension required in the cable
2- angular acceleration in rads/sec
3- Accelerating torque in Nm at the winding drum shaft required to accelerate the system
4- The total driving torque in Nm required at the winding drum shaft to produce the required motion of the whole system
I got 1 as 90,185N
2 - 1.33 rads/s
3- 5411Nm
4 is 5531Nm but I am not sure how to derive at this answer
The question then goes on to velocity time diagram like questions and asking for sketches
the hoist covers a distance of 20m accelerating at 0.8ms from rest to a max speed then decelerates at the same rate, i.e for 10m constant acceleration
the part of the question I am struggling with is where it asks for the maximum velocity of the hoist, this is 4ms but I am beat for knowing the calculation as I don't have an specific time, Could anyone help me with the formula required to achieve the answer of 4ms?
Many thanks!