# Calculate tension if acceleration given

#### bigman8424

a 70.0 kb man climbs vertical rope attached to ceiling. weight of rope is neglected. calculate tension in rope, if accelerate up rope at 0.40 m/s^2

T = m(g+a)
T = 70.0(9.8+.4)
= 714 N

slides downward acceleration of .40
T = m(g-a)
t = 70.0(9.8-.4)
= 685 N

looks good?

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#### whozum

Looks fine to me.

#### The Bob

bigman8424 said:
a 70.0 kb man climbs vertical rope attached to ceiling. weight of rope is neglected. calculate tension in rope, if accelerate up rope at 0.40 m/s^2

T = m(g+a)
T = 70.0(9.8+.4)
= 714 N

slides downward acceleration of .40
T = m(g-a)
t = 70.0(9.8-.4)
= 685 N

looks good?
Might just be me, but if he goes up at 0.4 then g is -9.8 because it is acting in the opposite direction. If you think about it in the direction as g is 9.8 then is acceleration is going to be -0.4.

So the second one looks good to me. #### whozum

The Bob said:
Might just be me, but if he goes up at 0.4 then g is -9.8 because it is acting in the opposite direction. If you think about it in the direction as g is 9.8 then is acceleration is going to be -0.4.

So the second one looks good to me. As he goes up he pulls down on the rope.

#### The Bob

whozum said:
As he goes up he pulls down on the rope.
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