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An object, when pushed with a net force F, has an acceleration of 4 m/s . Now twice the force is applied to an object that has four times the mass. Its acceleration will be 2 A. 1 m/s . 2 B. 2 m/s . 2 2 Which of the following pairs of acceleration of the blocks and tension in the rope is correct? A. Acceleration = 3.19 m/s2 and Tension = 702.5 N. B. Acceleration = 4.05 m/s2 and Tension = 297.5 N. C. Acceleration = 4.05 m/s2 and Tension = 702.5 N. D. Acceleration = 3.19 m/s2 and Tension = 297.5 N. C. 4 m/s D. 8 m/s E. None of the above.

User Steve G
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1 Answer

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Answer:

B. 2 m/s

B. Acceleration = 4.05 m/s² and Tension = 297.5 N.

Step-by-step explanation:

A force is applied on a mass m whose acceleration is 4 m/s

Force = mass × acceleration

a = F/m = 4 m/s

4 m/s = F/m

F = 4 m/s (m)

If Force of 2F is applied on a mass of 4m ; it acceleration is as follows:

2F/4 m = F/ 2m

4m/s (m) / 2m = 2 m/s

a = 2 m/s

2.

Given that

mass
m_1 = 30 kg

mass
m_2 = 50 kg


\mu = 0.1

From the question; we can arrive at two cases;

That :


m_(2) a _ \ {net} }= m_2g - T ----- equation (1)


m_(1) a _ \ {net} }= T - mg sin \theta - F ---- equation (2)

50 a = 50 g - T

30 a = T - 30 g sin 30 - 4 × 30 g cos 30

By summation

80 a =
[ 50 - 30 * (1)/(2) - 0.1 *30* (√(3))/(2)]g

80 a = 32. 4 × 10 m/s ² (using g as 10m/s²)

80 a = 324 m/s ²

a = 324/80

a = 4.05 m/s²

From equation , replace a with 4.05

50 × 4.05 = 50 × 10 - T

T = 500 -202.5

T =297.5 N

User Shannon Hochkins
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