Author Topic: physics: forces Question help needed  (Read 879 times)

Offline aiyla

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physics: forces Question help needed
« on: November 18, 2009, 07:02:10 pm »
1. a car of mass 1500kg tows a trailer of mass 2500kg. the driving force of the road on the wheels of the car is 7000N and both the car and the trailer experience resistive force of 1000N.

a) part A asked for acceleration and i got it  its 1.25ms-2
b) part b i dono :S

it says : "the tension in the coupling when the driving forces is reduced so that the acceleration falls to 1.00ms-2 is ?"

the answer is : 3500N .. but i can't figure it out why .




Offline MaNi_DaDuDe

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Re: physics: forces Question help needed
« Reply #1 on: November 18, 2009, 07:36:40 pm »
Try F = m x a

1. a car of mass 1500kg tows a trailer of mass 2500kg. the driving force of the road on the wheels of the car is 7000N and both the car and the trailer experience resistive force of 1000N.

a) part A asked for acceleration and i got it  its 1.25ms-2
b) part b i dono :S

it says : "the tension in the coupling when the driving forces is reduced so that the acceleration falls to 1.00ms-2 is ?"

the answer is : 3500N .. but i can't figure it out why .



Offline astarmathsandphysics

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Re: physics: forces Question help needed
« Reply #2 on: November 18, 2009, 08:58:17 pm »
F=ma
T-1000=2500*1
T=3500