The high-speed winds around a tornado can drive projectiles into trees, building walls, and even metal traffic signs. In a laboratory simulation, a standard wood toothpick was shot by pneumatic gun into an oak branch. The toothpick mass was 0.15 g, its speed before entering the branch was 212 m/s, and its penetration depth was 17 mm. If its speed was decreased at a uniform rate, what was the magnitude of the force of the branch on the toothpick? Number i Units +

As rock climbers ascend El Capitan over the course of 2 or 3 days, they have to bring all their food, water and camping equipment with them. All of this gear gets put in a large heavy duty bag and is hauled up after each section (called a pitch) that they climb. Climbers will generally climb a 50m pitch then stop and set up a pulley system to haul up the bag. If the rope has a mass of 0.05 kg per meter, the bag of gear has a mass 20kg and the rope is 50m long, how much work (in N-m) is required to pull up all the rope plus the haul bag?

In a two-dimensional tug-of-war, Alex, Betty, and Charles pull horizontally on an automobile tire at the angles shown in the picture. The tire remains stationary in spite of the three pulls. Alex pulls with force ₁ of magnitude 207 N, and Charles pulls with force Fc of magnitude 188 N. Note that the direction of Fc is not given. What is the magnitude of Betty's force if Charles pulls in (a) the direction drawn in the picture or (b) the other possible direction for equilibrium? 142° Alex Charles Betty (a) Number i (b) Number i Units Units <

In a two-dimensional tug-of-war, Alex, Betty, and Charles pull horizontally on an automobile tire at the angles shown in the picture. The tire remains stationary in spite of the three pulls. Alex pulls with force F A of magnitude 215 N, and Charles pulls with force F cof magnitude 181 N. Note that the direction of F cis not given. What is the magnitude of Betty's force F B if Charles pulls in (a) the direction drawn in the picture or (b) the other possible direction for equilibrium? Alex Charles 141° Betty (a) Number i Units (b) Number i Units

An object of mass 12.9 kg enters a rough floor with speed of 10.1 m/s. The coefficient of friction between the floor and the object is 0.30 and the object moves 2.07 m before returning to a smooth surface (frictionless). What is the velocity of the object once it returns to the smooth surface?

Many physical properties, such as force and mass, cannot be measured directly. Rather, some other physical property is measured and the desired physical property is computed from the results. For example, a bathroom scale does not actually measure mass or "weight," but rather the compression distance of a spring. The numerical values on the scale are calibrated from the compression distance using basic physics principles such as Newton's second law. Coefficients of friction cannot be measured directly. In this problem, we are going to learn how we can indirectly measure the coefficient of kinetic friction between two surfaces by directly measuring the expansion of a spring. Consider a 5.45 kg5.45 kg block that is dragged by a spring on a (relatively) frictionless horizontal surface at constant velocity. Suppose the block reaches a rough patch and the spring stretches by 5.25 cm5.25 cm. Compute the coefficient of kinetic friction ?μ between the block and the rough patch if the spring…

Two forces are exerted on an object: a force A with an x-component of 9.00[N] and a y-component of -2.40[N], and a force B with an x-component of -13.30[N] and a y-component of 23.60[N]. Assuming these are the only two forces on the object, what is the magnitude of the net force on the object? Express your answer in N.

The high-speed winds around a tornado can drive projectiles into trees, building walls, and even metal traffic signs. In a laboratory simulation, a standard wood toothpick was shot by pneumatic gun into an oak branch. The toothpick mass was 0.14 g, its speed before entering the branch was 221 m/s, and its penetration depth was 17 mm. If its speed was decreased at a uniform rate, what was the magnitude of the force of the branch on the toothpick?

Two identical springs, A and B, each with spring constant k = 30.7 N/m, support an object with a weight W = 15 N. Each spring makes an angle of θ = 34.8 degrees to vertical, as shown in the diagram.   (a) Write an expression for the tension in spring A (which is equal to the tension in spring B) in terms of W and θ.   (b) By how much is spring A stretched, in meters?

In a two-dimensional tug-of-war, Alex, Betty, and Charles pull horizontally on an automobile tire at the angles shown in the picture. The tire remains stationary in spite of the three pulls. Alex pulls with force F A of magnitude 214 N, and Charles pulls with force F c of magnitude 183 N. Note that the direction of F c is not given. What is the magnitude of Betty's force F B if Charles pulls in (a) the direction drawn in the picture or (b) the other possible direction for equilibrium? Alex Charles 145° Betty (a) Number i Units (b) Number i Units >