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9. A car is driving down the road at 15 m/s when the driver notices a stop sign up ahead. The driver applies the brakes and comes to a stop in 5 seconds. What was the acceleration of the car when the brakes were applied?
10. A rock drop-off 1250 feet building, has height s (in feet) above the ground at time t seconds given by s (t) = 1250 - 16t2. What is the instantaneous velocity of the rock at 5 seconds?
11. A particle is in motion and is accelerating. The functional form of the velocity is v (t) = 20t - 5t2. Find the instantaneous acceleration at t = 3 seconds.
12. You are riding your bike downtown at a speed of 15 m/s and you see a red light ahead. You gently brake over a distance of 50 m and come to a complete stop. What is your acceleration during this time?
6. We want to design an airport runway with the following specifications. The lowest acceleration of a plane should be 4 m/s2 and its take-off speed is 75 m/s. How long would the runway be to allow the planes to accelerate through it?
7. An object moving with a slowing acceleration along a straight line. After 10s and covering a distance of 60m, its velocity reaches 4m/s. What is its initial velocity?
8. Suppose the position of a particle is given by s (t) = 1 + 3t - 2t2, where t is in second and s is in meters.
a. Find the displacement using the time interval between t = 1 and t = 3.
b. Find the average velocity during the same time interval.
1. Renz is approaching a stoplight moving with a velocity of +30.0 m/s. The light turns yellow, and Renz applies the brakes and skids to a stop. If Renz acceleration is -8.00 m/s2, then determine the displacement of the car during the skidding process.
2. A car slows down its motion from 10 m/s to 6 m/s in 2 seconds under constant acceleration. What is its acceleration?
3. A car starts its motion from rest and uniformly accelerates at a rate of 4 m/s2 for 2 seconds in a straight line. How far did the car travel during those 2 seconds?
4. An object, without change in direction, travels a distance of 50 m with an initial speed of 5 m/s in 4 s. Find the object's velocity at the end of the given time interval?
5. Ben Simmons is waiting at a stoplight. When it finally turns green, Ben accelerated from rest at a rate of 6.00 m/s2 for a time of 4.10 seconds. Determine the displacement of Ben's car during this time period.
5. c) Find the total energy of a moving object of mass 6.3 kg and momentum 11.5*10^ 6 kgms^ -1 .
5. b) A matter has a body-centered cubic unit cell with a length of 330 pm along an edge and a density of 8.57 g cm^ -3 . Calculate the atomic mass of the matter.
4. c) If 12N force is applied to a fluid of cross-section 5.34 cm ^ 2 with a shearing rate of 0.7s ^ - 1 then find the viscosity of the fluid.
3. c) A wire of length 7 m and radius 2.37 mm is stretched by a load of 12370 gm and increased by 1.78% of the original length. Find the stress, strain, and Young's modulus of the material of the wire.
c) A capillary tube with an inside radius of 638 nm can support a 100 mm column of liquid that has a density of 820 kg * m ^ - 3 . The observed contact angle is 12.5 degrees . Find the surface tension of the liquid for h = 20 cm .
A 400.0-N sign hangs from the end of a uniform strut. The strut is 4.0m long and weighs 600.0N. The strut is supported by a hinge at the wall and by a cable a whoose other end is tied to the wall at point 3.0m above the left and of the strut. Find the tension in the supporting cable and the force of the hinge on the strut.
1. c) The radius of a silver bar is 30 cm. What force is required to stretch the bar by 12.7% of its length where Young's modulus is Y = 7.25 * 10 ^ 10 * N * m ^ - 2 .
