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3 years ago

15

A rubber-wheeled 50 kg cart rolls down a 35 degree concrete incline. Coefficient of rolling friction between rubber and concrete

is = 0.02. (a) What is the cart's acceleration if rolling friction is neglected? (b) What is the cart's acceleration if rolling friction is included?

1 answer:

lapo4ka [179]3 years ago

8 0

Answer:

(a) 5.62 m/s²

(b) 5.46 m/s²

Explanation:

The given values are:

mass,

m = 50 kg

angle

= 35°

(a)

If friction neglected,

⇒ $F_x=mgSin \theta=ma$

⇒ $a_x=gSin \theta$

$=9.8 \ Sin35^{\circ}$

$=5.62 \ m/s^2$

(b)

If friction present,

⇒ $F_x=mgCos \theta$

⇒ $F_x=mgSin \theta-\mu_r mgCos \theta$

⇒ $a=gSin \theta-\mu_rgCos \theta$

$=9.8 \ Sin35^{\circ}-0.02\times 9.8 \ Cos30^{\circ}$

$=5.46 \ m/s^2$

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