A car accelerates from rest to a maximum speed of 20 m/s over a 20 s time interval. The net force on the car as function of time is given by Fnet = 3350 (t + 1)-1/2 where Fnet is measured in N and t goes from 0 to 20 s. Multiple Choice Questions 7) What is the impulse on the car as it accelerates from rest to its top speed? a) 1.8 × 104 N. S b) 2.4 x 104 N.S c) 3.8 × 104 N s d) 4.1 x 104 N s e) 5.8 × 104 N. s f) 8.5 × 104 N. S 8) Assume that the wheels on the car each have a diameter of 49 cm and that the outside edge of the wheel spins with a tangential velocity of 20 m/s. If each of the wheels has a moment of inertia I = 0.75 kg. m², how much rotational kinetic energy does a single wheel have while traveling at this speed? a) O J b) 120 J c) 478 J d) 1913 J e) 2499 J f) 7653 J

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8. A force acts on a 5.4 kg object with the magnitude shown in Figure as a function of time. 2.0 438 1.5 € 1.0 0.5- 0 0.5 1.0 1.5 2.0 2.5 3.0 t(s) (a) Determine the impulse imparted by the force on the object. (b) Determine the final velocity of the object if it had an initial velocity of 24 m/s in the negative direction

A 3.0 kg object traveling 6.0 m / s east has a perfectly elastic collision with a 4.0 kg object traveling 8.0 m / s west. After the collision, the 3.0 kg object will travel 10.0 m / s to the west. a) What is the total moment before the collision? b) What is the total momentum of these objects after this collision?

3. The total external force on an object is F=10t i + 60j (N). At t=0, the objects velocity is V=20j (m/s). At t=12 sec., the x-component of its velocity is 48 m/s. a. Determine the mass of the object. b. Determine the impulse applied to the object from t=0 to t=6 sec. c. Determine the objects velocity at t=6 sec.

You push on a 50 kg shopping cart with a force of 15 N. If you push for 2.3 seconds, what is the magnitude of the impulse you deliver to the cart? * 34.5 N.s 70 N.s 6.52 N.s 48.3 N.s

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When a truck drives into a haystack, it doesn’t get damaged. When it drives into a concrete wall, there is a lot of damage. Both cases have the same initial speed for the truck and the same final speed as well. What is the difference between these two cases? A) The initial momentum is less when it strikes the haystack.B) The impulse is less when striking the haystack C) The change in momentum is less when striking the haystackD) Force of impact is less when striking the haystack   If you want to hit a volleyball without making it spin, you must apply a force A) Acting below the center of mass B) Acting above the center of massC) Acting through the center of massD) It is impossible to not make it spin