5. A toy sledge of mass 4 kg is being pulled in a straight line by a light string. The resistance to its motion is 6 N .
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\caption{Fig. 6.1}
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At one time, the string is horizontal and the sledge is on horizontal ground, as shown in Fig. 6.1. The acceleration of the sledge is \(3 \mathrm {~m} \mathrm {~s} ^ { - 2 }\) forwards.
- Calculate the tension in the string.
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\caption{Fig. 6.2}
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At another time, the sledge is again on horizontal ground but the string is now at \(40 ^ { \circ }\) to the horizontal, as shown in Fig. 6.2. The tension in the string is 25 N . - Calculate the acceleration of the sledge.
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\caption{Fig. 6.3}
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\caption{Fig. 6.4}
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In another situation the sledge is on a slope inclined at \(35 ^ { \circ }\) to the horizontal, as shown in Fig. 6.3. It is held in equilibrium by the light string parallel to the slope. The resistance to motion of 6 N acts up the slope. - Calculate the tension in the string.
The sledge is now held in equilibrium with the light string inclined at \(\theta ^ { \circ }\) to the slope, as shown in Fig. 6.4. The tension in the string is 25 N and the resistance to motion remains 6 N acting up the slope.
- (A) Show all the forces acting on the sledge.
(B) Calculate the angle \(\theta\).
(C) Calculate the normal reaction of the slope on the sledge.
\includegraphics[max width=\textwidth, alt={}, center]{fb36606d-0ee3-4050-af31-1642e5f67a03-17_2688_1886_118_118}