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A physics student (m = 78 kg) takes a scale into an elevator to try to measure the acceleration of the elevator.  As the elevator begins to descend from rest, the scale measures the student’s weight as 577.2 N.  Find the acceleration of the elevator.  

You will use this problem for Questions 13, 14, and 15. Read carefully. A pumpkin is launched from the ground level and is aimed at a 10.7 meter tall cliff some distance away.  The pumpkin is launched with an initial velocity of 18 m/s at an angle of 55° and it lands 5 m past the edge of the cliff. (a) How long (in seconds) is it in the air before it lands on the top of the cliff?  (b) How far away (in meters) is the cliff? (c) Find the maximum height of the pumpkin.

Imagine looking out at a beautiful sunset behind trees on the horizon. Then you look down at your phone to read a text message. How do the lenses of your eyes accommodate (change) to view a closer object? 

The gravitational pull of the moon is 1/6 that of the earth (about 1.6 m/s2).  One object weighs 30 N on Earth.  A second object weighs 30 N on the moon.  Which object has the greater mass? 

Which has zero acceleration? An object at rest                                                                d.  a, b, and c moving at constant velocity                             e.  none of these in mechanical equilibrium

The ___________________ is a vascular membrane lining the outer surface of the eye and the inner surface of the eyelids

Which neurons tend to be adrenergic?  

The diagram below represents the neural layer of the retina in the eye Which photoreceptor provides the sharpest/clearest vision? (Type the letter not the name)  

You will use this problem for Questions 5 and 6.  Read carefully!  Free body diagrams will be graded in the written work. An apple crate has a weight of 225 N, and is moved across the floor by the 2 forces directed as shown in the diagram. (a)  Draw a free body diagram on your paper.  Use that diagram to find the normal force on the crate. (b)  If μk = 0.12, find the horizontal acceleration of the crate across the floor. For this question, enter the answer to part (b) – the acceleration of the crate.

You will use this problem for Questions 7 and 8.  Read carefully!  Free body diagrams will be graded in the written work. Mass 1 sits on a frictionless table, and mass 2 is attached to mass 1 by a string laid over a pulley as shown in the diagram. If a force of 10 N pulls on mass 1 as shown, (a) find the acceleration of the blocks and (b) find the tension in the string. For this question, enter the answer for part (b) – the tension in the string.