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3 years ago

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A 75-g mass sits 75 cm from the center of a rotating platform undergoing a uniform angular acceleration of 0.125 rad/s^2. The co

efficient of static friction between the mass and the platform is 0.250.
What is the speed of the mass when it slides off?
a. 0.889 m/s
b. 1.36 m/s
c. 1.44 m/s
d. 1.58 m/s
e. It will never slide off.

1 answer:

jasenka [17]3 years ago

3 0

Answer:

velocity of mass when it slides of will be 1.36 m/sec

So option (b) will be correct option.

Explanation:

We have given mass of the slits m = 75 gram = 0.075 kg

Radius r = 75 cm = 0.75 m

Coefficient of kinetic friction $\mu =0.250$

Acceleration due to gravity $g=9.8m/sec^2$

When the mass slides of

$\frac{mv^2}{r}=\mu mg$

$v=\sqrt{\mu rg}=\sqrt{0.250\times 0.75\times 9.8}=1.36m/sec$

So velocity of mass when it slides of will be 1.36 m/sec

So option (b) will be correct option.

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3 years ago