By how much does the force required to stop a car increase if the initial speed is doubled and the stopping distance remains the same? (b) How far must the faster car travel before it has a 15-min lead on the slower car? Consider a car of mass 1669kg whose tires have a static friction coefficient 0.86 against the pavement. A football player runs from his own goal line to the opposing teams goal line, returning to the fifty-yard line, all in 18.0 s. Calculate (a) his average speed, and (b) the magnitude of his average velocity. Solutions Verified Solution A Solution B Answered 1 year ago Create an account to view solutions Recommended textbook solutions B) How would your ans, A car travels along a straight, level road. A record of travel along a straight path is as follows:1. Does either driver hear a different frequency from the other car's horn than they would if the cars were stationary? Assuming they start at the same point, how much sooner does the faster car arrive at a destination 12 mi away? {eq}\displaystyle \Delta T = t_s - t_f = \frac 9{55}\text{h}-\frac 3{20}\text{h}=\frac{180-165}{1100} \ \text{h} = \frac{15}{1100}\text{h}=\frac 3{220} \ \text{h}=\frac 3{220}\text{h}\cdot \frac{3600\text{ sec}}{\text{h}}\boxed{\approx 49\text{ sec}} (b) What initial velocity must the second stone have had, given that they hit the water simultaneously? What was the final velocity of the car (in m/s)? If no, determine the distance of closest approach between Sues car and the van. Solution: The time of motion for faster car 1= 1 = 12 . For the first 5.0 s of the car's motion, the eastward component of the car's velocity is given by vx(t) = (0.840 m/s^3)t^2. (There are 5,280 ft in one mi. . Calculate the (a) acceleration of the car, (b) the distance traveled during this time. A highspeed camera records this event. The second car starts from rest and has a constant acceleration. Find the rate of the slower car if one car travels at a rate 20 miles per hour faster than the other. Two cars emerge side by side from a tunnel. How long did the car take to stop? hb``g``jb P#0p4 C1C*?%rvrn3>gZbhCgL>pmP4a7 b4{0 ITX B"
For the next 3.36 seconds, the car slows down further, and its average acceler, At time t = 0 a car moving along a straight line has a velocity of 16 m/s. Submit order In a race, they both start at the same time, but the hare stops to rest for 2.0 minutes. (c) What was the velocity of each stone at the instant it hit the water? (c) Will doubling the time always double the change in speed? Two cars travel in the same direction along a straight highway, one at a constant speed of \( 55 \mathrm{mi} / \mathrm{h} \) and the other at \( 60 \mathrm{mi} / \mathrm{h} \). Austin drives his car with an average velocity of 35.0 km/h to the east. What is the c. What is the speed of a car if it travels 200 meters in 30 seconds? In order for that to happen, at some point they would have had to pass each other along the way, and when they passed each other neither would have traveled 810km . (b) How fast was the jumper traveling upon impact with the river? (c) How long after liftoff does the rocket reach its maximum height? (a) Find the trucks original speed. endstream
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If the brakes are applied for $3.0 {s},({a})$ how fast is the car going at the end of the braking period, and (b) how far has the car gone? How fast is the plane g. When the speed of a moving car is doubled, how much more kinetic energy does it have? mi BIO The average person passes out at an acceleration of 7g (that is, seven times the gravitational acceleration on Earth). 0
It accelerates at 4.6 m/s^2 for 7.2 s, coasts for 1.9 s, and then slows down at a rate of 2.5 m/s^2 for the next stop sign. A graph of position versus time for a certain particle moving along the x - axis is shown in Figure P2.6. (d) What is the total distanceit travels during the interval in part (c)? At the end of 3 hours, they are 300 miles apart. Time = Distance / Speed Speed = Distance / Time Distance = Time Speed To convert minutes into hour, we should divide the given minutes by 60. Two cars travel in the same direction along a straight highway, one at a constant speed of 55 mi/h and the other at 70 mi/h. (a) Assuming that they start at the same point, how much sooner does the faster car arrive at a destination 10.0 miles away? A student throws a set of keys vertically upward to his fraternity brother, who is in a window 4.00 m above. Turnaround times are negligible, and the boat that completes the round trip first wins. If the acceleration is constant, how much time elapses while the auto moves the 180 ft? For any two points there's exactly one line segment connecting them. (b) How long does it take the aircraft to become airborne? What will its velocity be 1 and 5 seconds later? (a) How long does it take the boat to reach the buoy? Two boats start together and race across a 60-km-wide lake and back. How far will it travel in meters? She drives for 50.0 minutes at 60.0 km/h, 9.0 minutes at 95.0 km/h, and 55.0 minutes at 35.0 km/h. {/eq}, Setting the time difference {eq}t_s-t_f A) What distance does the first vehicle travel while the driver is reacting? State how you decide. {/eq}: (a) Let's designate the two cars by the subscripts 'f' for 'faster', and 's' for 'slower'. It accelerates at 3.6 m/s 2 for 5.0 s and then coasts for 10 s. (a) What is its maximum speed? \( \times \min \) (b) How far must the faster car travel before it. Boat B goes across at 30 km/h, and its crew, realizing how far behind it is getting, returns at 90 km/h. b. do the two cars have the same velocity? Assume that it takes 5.0 seconds to decelerate. The first stone had an initial velocity of 22.00 m/s. Two cars travel in the same direction along a straight highway, one at a constant speed of 55 mi/h and the other at 70 mi/h. and {eq}\displaystyle t_s = \frac d{s_s}=\frac{9\ \text{mi}}{55\ \text{mi/h}} = \frac 9{55} \ \text{h} Suppose a small child rolls off a bed that is 0.40 m above the floor. Two cars B and C approach car A in opposite directions with a speed of 54 km h -1 each. in km? A car is moving east at 100 km/h is brought to rest in 0.80 s. a. (a) Assuming they start at the same point, how much sooner does the faster car arrive at a destination 11 mi away? It would seem to make sense to say that speeding up from 0 km/h to 30 km/h would take just as much energy as speeding up from 30 km/h. She holds the bill vertically as in Figure P2.67, with the center of the bill between Davids index finger and thumb. (a) Assuming they start at the same point, how much sooner does the faster car arrive at a destination 10 mi away? How long does it take the cheetah to run the first 82 m? What would have been the unrealistically large acceleration experienced by the space travelers during their launch? P2.56). min 1 See answer Advertisement thedemon840 Answer: The first car arrives (33 seconds or 0.55 minutes) earlier Express the answer in terms of an angle (in degrees) and a distance. Educator app for Speedy Sue, driving at 30.0 m/s, enters a one-lane tunnel. You are driving at the speed of 33.5 m/s (74.9534 mph) when suddenly the car in front of you (previously traveling at the same speed) brakes and begins to slow down with the largest deceleration possi. The units of x would be dollars ($), and velocity v would give the rate at which the balance changes (in units of, for example, $/month). Suppose a person begins with ten thousand dollars in the bank. The speed of a nerve impulse in the human body is about 100 m/s. The relationship between distance, speed and time. If the hare then begins running with constant speed $v_{1}$ and the tortoise continues crawling with constant speed $v_{2},$ it turns out that the tortoise wins the race if the distance $L$ is less than $\left(v_{2} /\left(v_{1}-v_{2}\right)\right) d$ . Explain physically why or why not. *37. mmh A car is traveling at a constant speed of 33 m/s on a highway. A ball thrown straight up into the air is found to be moving at 1.50 m/s after rising 2.00 m above its release point. If his reaction time is 0.2 s, will he succeed? Why is a car driving around a circular track with a constant speed of 100 km/h accelerating even though its speed is constant? The velocity of a toy car is plotted in the graph below. In a test run, a certain car accelerates uniformly from zero to 24.0 m/s in 2.95 s. (a) What is the magnitude of the cars acceleration? a. Disregard the width of the crossing. He drives at this speed for another 20 s, and then slows to a stop over a distance of 500 m. (a) What is the trip? T A hockey player is standing on his skates on a frozen pond when an opposing player, moving with a uniform speed of 12 m/s, skates by with the puck. What was the average velocity? \mathrm{km} / \mathrm{h}$ on a track with a total length of $1.60 \times 10^{3}$ . (b)What is his average velocity? The cheetah can reach a top speed of 114 km/h (71 mi/h). A race car starts from rest and travels east along a straight and level track. Two cars travel in the same direction along a straight highway, one at a constant speed of 55 mi/h and the other at 70.0 mi/h. Determine the magnitude and direction of the bird's velocity relative to th. Expl. If the initial speed of the bullet is $4.00 \times 10^{2} {m} / {s}$ and it emerges from the other side of the board with a speed of $3.00 \times 10^{2} {m} / {s}$ , find (a) the acceleration of the bullet as it passes through the board and (b) the total time the bullet is in contact with the board. Emily challenges her husband, David, to catch a $1 bill as follows. b. The faster truck is going 2mph faster than the slower truck. How far did it travel? Find the balls initial speed. Obtain this result by first writing expressions for the times taken by the hare and the tortoise to finish the race, and then noticing that to win, $t_{\text { tortoise }} Marcus Theaters Employee Handbook,
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