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3 years ago

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A semi-trailer is coasting downhill along a mountain highway when its brakes fail. The driver pulls onto a runaway truck ramp th

at is inclined at an angle of 17.0° above the horizontal. The semi-trailer coasts to a stop after traveling 160 m along the ramp. What was the truck's initial speed?

1 answer:

aleksklad [387]3 years ago

6 0

<u>Answer:</u>

The velocity is 30.279 m/s

<u>Explanation</u>:

Consider the initial speed of the semi-trailer be v

Then, initial kinetic energy = $\frac{1}{2} mv^2$

According to question, the semi-trailer coast along a ramp, which is inclined at an angle of 170, and to a distance of 160m to stop

Change in vertical position = $h=160 \times \sin 17^{\circ}-0$ = 46.779m

Final potential energy of semitrailer = mgh

Applying principle of conservation of energy,

$\frac{1}{2} mv^2$ = mgh

Solving for v, we get $v^2$ = 2gh = 2*9.8*46.779 = 916.8684

$v^2$ = 916.8684

v = 30.279 m/s

Therefore, the velocity is 30.279 m/s

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To solve this problem we will use the relationship given between the centripetal Force and the Force caused by the weight, with respect to the horizontal and vertical components of the total tension given.

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Here,

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Matching both expressions with respect to the tension we will have to

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Then we have that,

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Answer:

a. FALSE

b.TRUE

C. FALSE

Explanation:

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