a) What is the mechanical advantage of a wheelbarrow, such as the one in Figure 9.24, if the center of gravity of the wheelbarrow and its load has a perpendicular lever arm of 5.50 cm, while the hands have a perpendicular lever arm of 1.02 m? (b) What upward force should you exert to support the wheelbarrow and its load if their combined mass is 55.0 kg? (c) What force does the wheel exert on the ground?
Solution 21PE Step-by-step solution Step 1 of 7 (a) The free body diagram of the wheel barrow is: Step 2 of 7 The expression to find the mechanical advantage of the wheel barrow is: Here is length of perpendicular lever arm and is the length of the perpendicular lever load. Substitute for and for in the expression of mechanical advantage, Hence, Mechanical advantage of a wheelbarrow is . Step 3 of 7 (b) The expression to find the mechanical advantage of the wheel barrow is: Here is the force required to support the wheelbarrow, and is output force, Rearrange the expression to find input force, The output force in the wheel-borrow is same as the weight due to combined mass of wheel barrow and load. Now, the expression of the input force is: Step 4 of 7 The expression to find the weight is: Combine the expression of the weight and input force: Substitute for , for and for in the above expression,