Minty wants to increase the heat transfer between a metal iron and other piece of metal he wants to shave. He decides to increase the time the two metals are in contact, use a large metal iron, and use a new metal material with a higher specific heat. Where is month’s error?

Abaseball picther can throw a ball at about 90 miles per hour, v = 40 m/s, on solid rock ground. we now put him into space. when he throws the ball, which weighs mb = 0.15 kg moves away from himat the same speed. how long does it take the ball thrown in space to travel the 30 meters to the batter? he weighs mp = 100kg

Abaseball has a mass of 0.145 kg and approaches a bat at 40.0 m/s. after it is hit, the ball leaves the bat at 50.0 m/s directly back. find the impulse of the bat on the ball. 7.25 kg*m/s 13.1 kg*m/s 5.80 kg*m/s 1.45 kg*m/s

Aheat engine running backward is called a refrigerator if its purpose is to extract heat from a cold reservoir. the same engine running backward is called a heat pump if its purpose is to exhaust warm air into the hot reservoir. heat pumps are widely used for home heating. you can think of a heat pump as a refrigerator that is cooling the already cold outdoors and, with its exhaust heat qh, warming the indoors. perhaps this seems a little silly, but consider the following. electricity can be directly used to heat a home by passing an electric current through a heating coil. this is a direct, 100% conversion of work to heat. that is, 19.0 \rm kw of electric power (generated by doing work at the rate 19.0 kj/s at the power plant) produces heat energy inside the home at a rate of 19.0 kj/s. suppose that the neighbor's home has a heat pump with a coefficient of performance of 4.00, a realistic value. note: with a refrigerator, "what you get" is heat removed. but with a heat pump, "what you get" is heat delivered. so the coefficient of performance of a heat pump is k=qh/win. an average price for electricity is about 40 mj per dollar. a furnace or heat pump will run typically 200 hours per month during the winter. what does one month's heating cost in the home with a 16.0 kw electric heater? what does one month's heating cost in the home of a neighbor who uses a heat pump to provide the same amount of heating?