Question

A cyclist is riding with a speed of 43.2 km/h. As he approaches a circular turn on the road of radius 60 m, he applies brakes and reduces his speed at constant rate of 1.8 ms^-2. The magnitude of the net acceleration of the cyclist is ______.

पर्याय

• 1 ms^-2

• 0.5 ms^-2

• 3 ms^-2

• 1.5 ms^-2

Answer 1

A cyclist is riding with a speed of 43.2 km/h. As he approaches a circular turn on the road of radius 60 m, he applies brakes and reduces his speed at constant rate of 1.8 ms^-2. The magnitude of the net acceleration of the cyclist is 3 ms^-2.

Explanation:

`"a"_"R"` = `"v"^2/"r" = (((43.2 xx 10^3)/3600))/60= (12)^2/60`

= 2.4 m/s²

Given that,

`"a"_"T"= 1.8 m/s^2`

` "a" = sqrt("a"_"R"^2 + "a"_"T"^2`

`= sqrt((2.4 )^2 + (1.8)^2`

`= sqrt(5.76 + 3.24)`

`= sqrt(9)`

= 3m/s²