You push downward on a trunk at an angle 25° below the horizontal with a force of 750 N.If the trunk is on a flat surface and the coefficient of static friction is 0.76,what is the most massive trunk you will be able to move? (Use g = 9.8 m/s². ) A)59 kg B)68 kg C)54 kg D)82 kg

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The force of friction is given by:$$f_s=\mu_sn$$where:* $f_s$ is the force of friction* $\mu_s$ is the coefficient of static friction* $n$ is the normal forceThe normal force is equal to the force applied perpendicular to the surface:$$n=F\cos	heta$$where:* $F$ is the applied force* $	heta$ is the angle between the applied force and the surfaceThe maximum force of friction is equal to the coefficient of static friction times the normal force:$$f_s=\mu_sn=0.76F\cos25^\circ$$The maximum force that can be applied without moving the trunk is equal to the force of friction:$$F=f_s=0.76F\cos25^\circ$$Solving for $F$, we get:$$F=\frac{f_s}{\cos25^\circ}=\frac{0.76F}{\cos25^\circ}=0.85F$$Therefore, the maximum force that can be applied without moving the trunk is 0.85 times the applied force. The applied force is 750 N, so the maximum force that can be applied without moving the trunk is:$$F=0.85(750	ext{ N})=637.5	ext{ N}$$The mass of the trunk is equal to the force applied divided by the acceleration due to gravity:$$m=\frac{F}{g}=\frac{637.5	ext{ N}}{9.8	ext{ m/s}^2}=65	ext{ kg}$$Therefore, the most massive trunk that can be moved is 65 kg.

You Push Downward on a Trunk at an Angle 25°