A 20.0-g ball hangs from the roof of a freight car by a string. When the freight car begins to move, the string makes an angle of 35.0° with the vertical. (a) What is the acceleration of the freight car? (b) What is the tension in the string?

Respuesta :

Answer:

(a) [tex]a=6.883m/s^{2}[/tex]

(b) [tex]T_{tension}=0.24N[/tex]

Explanation:

Given data

Angle α=35.0°

Mass m=20g=0.02 kg

To find

(a) Acceleration a

(b) Tension T

Solution

For part (b) tension T

From Newtons Second Law the Tension on string is given b[tex]T_{tension} Cos(\alpha )=W_{weigth}\\T_{tension}Cos(\alpha )=m_{mass}g_{gravity}\\T_{tension}=\frac{m_{mass}g_{gravity}}{Cos(\alpha )}\\T_{tension}=\frac{0.02kg*9.8m/s^{2} }{Cos(35^{o} )}\\T_{tension}=0.24N[/tex]

For part(a) acceleration

The acceleration is given by:

[tex]F=ma=TSin(\alpha )\\ma=TSin(\alpha )\\a=\frac{TSin(\alpha )}{m}\\ a=\frac{(0.24N)Sin(35 )}{0.02kg}\\a=6.883m/s^{2}[/tex]