Final answer:
To exert a torque of -13 N·m with a wrench tilted at 30° and 35 cm long, Luis must apply a force of 74.29 N downward on the wrench.
Step-by-step explanation:
The student is asking how to calculate the force required to apply a specific torque when pulling down on a wrench. Given that the torque (τ) is -13 N·m, the wrench length (r) is 35 cm (which is 0.35 m), and the angle (θ) above the horizontal is 30°, we can use the formula for torque, τ = rFsinθ, where F is the force applied.
We can rearrange the formula to solve for F: F = τ / (rsinθ). Plugging in the given values, F = -13 N·m / (0.35 m × sin(30°)) = -13 N·m / (0.35 m × 0.5) = -13 N·m / 0.175 m = -74.29 N. Since a negative force doesn't make physical sense in this context, we take the absolute value and conclude that Luis must apply a force of 74.29 N.
In summary, to exert a torque of -13 N·m by pulling straight down on the tilted wrench, Luis must apply a force of 74.29 N.