An advertisement shows a 1239 kg1239 kg car slowly pulling at constant speed a large passenger airplane to demonstrate the power of its newly designed 63.7 hp63.7 hp (horsepower) engine. During the pull, the car passes two landmarks spaced 25.0 m25.0 m apart in 14.3 s.14.3 s. The passenger plane being towed is a Boeing 707 with a total weight of 62.5 tons.62.5 tons. Calculate the force that opposes the motion. Assume that the efficiency of the car is such that 24.2%24.2% of the engine power is available to propel the car forward. How much work is performed by the car on the airplane during this time?How much work is performed by the airplane on the car during this time?

A trap-jaw ant snaps its mandibles shut at very high speed, a good trait for catching small prey. But an ant can also slam its mandibles into the ground; the resulting force can launch the ant into the air for a quick escape. A 12 mg ant hits the ground with an average force of 47 mN for a time of 0.10 ms; these are all typical values. At what speed does it leave the ground? Answer out to 3 decimal places.

The Top Thrill Dragster at Cedar Point amusement park in Sandusky, Ohio, is one of the world’s most impressive roller coasters. Wearing only a lap harness in the open air, riders on a 10.5-ton train are accelerated by hydraulic motors on a level track to 120 mph in just 3.8 s. After this, no more power is supplied to the train, and it moves on its own. The train shoots straight up (twisting along the way) along the track to a height of 420 ft, before a straight-down descent. Calculate the kinetic energy of the train after the 3.8-s launch. Round the final answer to two decimal places.

A stray dog catcher drives 34km east, picks up some dogs, then drives 10km west to drop them off before continuing east for 21km. 30N of force is being applied constantly parallel to the dog catcher's motion. Solve for the work the dog catcher has accomplished.

rough surfice Smath swace leeeeed 2.50m he 3.00m E; Ei + WNc A 34.2 kg block slides with a velocity of 10.22 m/s to the right on a frictionless surface (as shown in the figure above). The block slides up a slope to a height of 3.00 m and then slides across a 2.50 m long rough surface with a coefficient of kinetic friction equal to 0.325. The block continues to travel to the right and bumps into a massless spring with a spring constant (k) equal to 2320 N/m. a) How much does the spring get compressed by the block with respect to its equilibrium length? Please answer with a positive number in units of metres, with 3 sig figs. Start with conservation of energy: E, = E; + WNC , and show all steps. b) What is the potential energy stored by the spring when the mass comes to a stop? Please show the symbolic equation and then "plug in the numbers" to give a numerical answer in units of joules with 3 sig figs. c) What happens to the potential energy stored in the spring after the block stops…

44. A 15 kg child slides, from rest, down a play- ground slide that is 4.0 m long, as shown in the figure. The slide makes a 40° angle with the horizontal. The child's speed at the bot- tom is 3.2 m/s. What was the force of friction that the slide was exerting on the child? 傳 4.0 m 40°

A stuntman with a mass of 87.0 kg swings across a moat from a rope that is 11.5 m. At the bottom of the swing the stuntman's speed is 7.95 m/s. The rope's breaking strength is 1,000 N. Will the stuntman make it across the moat without falling in? Yes/No       (b)What If? What is the maximum speed (in m/s) that the stuntman can have at the bottom of the swing on this vine to safely swing across the river? m/s