(a) An automobile having a mass of 900 kg initially moves along a level highway at 100 km/h relative to the highway. It then climbs a hill whose crest is 50 m above the level highway and parks at a rest area located there. For the automobile, determine its changes in kinetic and potential energy, each in kJ. For each quantity, kinetic energy and potential energy, specify your choice of datum and reference value at that datum. Let g = 9.81 m/s².

Nhand,A 75 N ma = 3 kg %D VA = 8 m/s Block Block Block Block B A Hx = 0.4 %3D 2 m Ax Note: Diagram is not drawn to scale A hand pushes block A (m,= 3 kg) with a constant force Nand. A= 75 N for a distance Ax 2 m along a (mostly) frictionless table such that it speeds up from rest and is traveling at a speed of 8 m/s after it slides over a rough section of the table (H = 0.4). Block A then collides with a more massive block B (mg = 6 kg) that is initially at rest. Find the speed of block A after it has been released by the hand and just before the rough section of the table. A) 10 m/s B) 20 m/s C) 30 m/s D) 40 m/s E) 50 m/s O A O B O D O E

A teacup fell was left on the wing of a fighter jet and did not fall until the jet was already very high up and very fast. After falling for some time it has reached a constant velocity of 55 m/s. The mass of the teacup is 237 g. What is the net force acting on the teacup? * 13,035 N ON 13.035 N 4.31 N

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70 Energy (Joule) ☎ 8 8 8 8 8 8 50 30 10 o S2FRT820 $2FRT730 AS2FRT650 S2HT940 o $2HT1150 0 -200 -150 S2FRT820 O -100 + S2HT940 A -50 0 Temperature (°C) O O S2FRT730 ... S2FRT650 $2HT1150 50 100 The figure shown corresponds to the absorbed energy of different ferritic steels in a temperature range of 1. What is the ductile-brittle transition temperature of S2FRT730 steel? 2. If a component will work at -50°C, what materials (from those shown) would you use to manufacture it? EXPLAIN YOUR ANSWER.

An automobile having a mass of 1100 kg initially moves along a level highway at 110 km/h relative to the highway. It then climbs a hill whose crest is 40 m above the level highway and parks at a rest area located there. Use a reference with kinetic and potential energy each equal to zero for the stationary highway before the hill.Let g = 9.81 m/s2. For the automobile, determine its change in kinetic energy and its change in potential energy, both in kJ.

4. Directions: Complete the "Energy Table" for the roller coaster shown below Mass = 6500 kg H %3D G. 120m D E 120m 60m F 40m 立 POINT HEIGHT (m) VELOCITY (m/s) ME (J) PE (J) KE (J) 120 20320 B 60 4550000 E 40 F G 3000000

A rope pulls a 200 kg sleigh up a slope at incline angle θ=30 deg, through distanced=20m. The sleigh and its contents have a total mass of 200kg. The snowy slope is soslippery that we take it to be frictionless. How much work is done by each force(Normal, gravitational, rope’s) acting on the sleigh?

Two blocks of mass m are brought close to each other with a spring (mass negligible) compressed between then. The spring has potential energy 1/2kx2, where k and x are the force constant and the compression of the spring. The system is held together by a string (mass negligible) that opposes the outward force of the spring. When the string is cut, the spring expands to to its natural length (where it stores no more potential energy), and the two blocks fly apart with total kinetic energy equal to the potential energy that had been stored in the spring. In terms of the mentioned quantities, find the mass of the system before the string was cut.

An automobile moving at a constant velocity of 45 ft/s passes a gasoline station. Two seconds later, another automobileleaves the gasoline stationandaccelerates at the constant rate of 6 ft/s2. How soon will the second automobile overtake the first?