Question

On its own, a tow truck has a maximum acceleration of 4.0 m/s2. What will be its maximum acceleration when the truck is using a light horizontal chain to tow a bus of four times its own mass?

a. 1.0 m/s^2

b. 1.5m/s^2

c. 8.0m/s^2

d. 2.0m/s^2

e. None of the above

Answer 1

let the force working on the truck be F, and mass of the truck be m. Acceleration of the truck is 4 m/s2.

so using Newton's second law that is- F = ma ( force = mass x acceleration) that gives

F = 4m .................................... (1)

now when the bus is towed to the truck the new mass is = mass of truck + mass of bus

= m + 4m = 5m

as the force is same in the given case so let the acceleration of the system be x then

F = 5mx ...............................(2)

equating equation 1 and 2 we get

5mx = 4m

that gives x = 4/5

x = 0.8 m/s2

which is not a option of the given solutions ..... there for opt option E (none of the above)

thanks .............