A store is thrown horizontally and follows the path XYZ shown. The direction of

Question

A store is thrown horizontally and follows the path XYZ shown. The direction of the acceleration of the store at point Y is: A toy racing car moves with constant speed around the circle shown below. When it is at point A its coordinates are x = 0, y = 3 m and its velocity is(6 m/s). When it is at point B its velocity and acceleration are: A) (-6 m/s)j and (12 m/s^2)i, respectively B) (-6 m/s)j and (-12 m/s^2)i, respectively C) (6 m/s)j and (12 m/s^2)i, respectively D) (6 m/s)i and (-12 m/s^2)j, respectively A 50.0-N box is sliding on a rough horizontal floor, and the only horizontal force acting on it is friction. You observe that at one instant the box is sliding to the right at 1.75 m/s and that it slops in 2.25 s with uniform acceleration. What is the magnitude of the coefficient of kinetic friction? A) 0.13 B) 0.40 C) 0.08 D) 0.37

Explanation / Answer

(5) Option (A) is the correct answer. The acceleration acting on the stone is gravitational acceleration (g) which always acts in the downward direction.

(6) At point B, velocity is in the downward direction that is, -y-axis.

Magnitude of velocity is constant.

So, its value = (-6)j

Acceleration = v^2/R = (-6)^2/3 = 12 m/s^2

and its direction is always towards the center (+i direction).

So, option (A) is the correct answer.

(7) initial velocity, V = 1.5 m/s

t = 2.25 s

so, acceleration, a = V/t = 1.5/2.25 = 0.67 m/s^2

Now, a = mu*g

=> mu = a/g = 0.67/9.81 = 0.07

This value is nearest to the value 0.08.

So, option © is the correct answer.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.