Question

(1 point) A soccer ball is thrown straight up a distance of 6.0 m and retums to your hand. Neglecting air resistance, you know that OA. the accelcration was constant throughout its motion B, the acceleration wฮ5 upward on the way up and downward on the way down О С, the speed was zero at the maximum height, but the velocity was never zero. D. the ball took longer to go up than come down. E. the velocity was constant except at the moment it turned around (1 point) 0 Rank in order, from most postive to least positive, the accelerations at points A to C on the graph above A. C B A (1 point) In a recent television broadcast, an astronaut was shown to be weightless' while on a visit to the Intemational Space Station which orbits Earth. This can be explained by the fact that 0 A, tne astronaut and the space shuttle are both in tree tall OB. the force or gravity exerted on the astronaut by Earth is balanced by the force of gravity exerted on the astronaut by the sun О С·the space shuttle is going so tast that the torce of gravity exerted on the astronaut by Earth does not need to be considered. D. the force of gravity exerted on the astronaut by Earth is zero. E. the force of gravity exerted on the astronaut by Earth is balanced by the force of gravity exerted on the astronaut by the space shuttle (1 point) A muscle tendon with a circular cross-section of diameter d and length L is stretched by an amount ΔL by a steady force F How much stretch would an equal force produce in a similar tendon of diameter 2d and length 2 L? D. 2AL (1 point) A length or bone Escompressed to its fracture point by a force of 6600 N. The force required to compress a onger length of the same bone to its fracture point is OA. time dependent OB, unable to tell C. smaller than 6600 N. D. larger than 6600 N E. equal to 6500 N (a) θ (1 point) Which one of the graphs in the image above represents the dependence of the twist-angle θ on the length Z of a solid rod of radius r, when the torque causing the twist is the same for all lengths A. (a) B. (b) C. (C) D. (d) (1 point) The shear modulus or bone is 9 × 109 N/m2, or copper 4 × 1010 Nrm2, and or aluminum 2.5 × 1010 N/m2. For identical pieces same dimensions) of these materials, which one would twist most easily? Rank in order from easiest to most difficult A. Bone, copper, aluminum B. Bone, aluminum, copper C. Aluminum, bone, copper

Answer 1

i) force acting on ball is downward so, f = ma, acceleration of ball is downward in throughout the motion. A == -g m/s^2 option 'A' is correct (ii) slope of v.t graph = a A = positive B = 0 c = negative A > B > C option B is correct