A skateboarder travels down a curved path, ending up at a lower height than where he started. Which statement is correct about the work on the skateboarder by the normal force and by the force of gravity?
Answer:
the following statement is correct about the work on the skateboarder by the normal force and by the force of gravity:
Work done by the normal force is Zero, Because Normal force always acts perpendicular to the direction of motion.
A skateboarder travels down a curved path, ending up at a lower height than where he...
A skateboarder with mass m_ s = 52 kg is standing at the top of a ramp which is h_ y = 3.6 m above the ground. The skateboarder then jumps on his skateboard and descends down the ramp. His speed at the bottom of the ramp is v_ f= 6.8 m/s. Randomized Variables m_ s= 52 kg h_ y = 3.6 m V_ y= 6.8 m/s Write an expression for the work, w_ f, done by the friction force...
Problem A car travels at a constant speed of 29.5 mi/h (13.2 m/s) on a level circular turn of radius 46.0 m, as shown in the bird's-eye view in Figure 7.13a. What minimum coefficient of static friction, Aus, between the tires and the roadway will allow the car to make the circular turn without sliding? Strategy In the car's free-body diagram (Fig. 7.13b) the normal direction is vertical and the tangential direction is into the page (step 2). Use Newton's...
Example 7.7 Buckle Up for
Safety
Goal Calculate the frictional force that
causes an object to have a centripetal acceleration.
Problem A car travels at a constant speed of 31.5
mi/h (14.1 m/s) on a level circular turn of radius 55.0 m, as shown
in the bird's-eye view in Figure 7.13a. What minimum coefficient of
static friction, µs, between the tires and the
roadway will allow the car to make the circular turn without
sliding?
Strategy In the car's free-body...
There’s two boxes of equal mass: one pulled up by a rope at constant speed, and another pulled up a ramp at a constant speed. They’re pulled up to the same height and there’s no friction on the ramp. Which statement is true? A) the magnitudes of force of tension in ropes are equal b) the work done by tension of rope in system 1 (the one being pulled up) is smaller than system 2 (the ramp one) C) the...
1. A kid is pulling on a lawnmower with an applied force FA that is 30° with respect to the horizontal. Which statement is true about the normal force acting on the lawnmower? (5 pts) A. The normal force acting on the block N = 0, 300 B. The normal force acting on the block N < mg. C. The normal force acting on the block N > mg. D. The normal force acting on the block N = mg....
5. Problems 2.5 The height of a ball that is thrown straight up with a certain force is a function of the time (t) from which it released given by At)--0.5 g40r (where g is a positive constant determined by gravity) The time at which the ball is at its maximum height depends on the parameter g, and is given by * Substituting t* back into the function f(t) yields f(t*) - dfíi*) ,the derivative (with respect to g) of...
A civil engineer wishes to redesign the curved roadway in the figure in such a way that a car will not have to rely on friction to round the curve without skidding. In other words, a car moving at the designated speed can negotiate the curve even when the road is covered with ice. Such a ramp is usually banked, which means that the roadway is tilted toward the inside of the curve. Suppose the designated speed for the road...
A young work crew is trying to quickly finish some touch-up painting to complete a job. Rather than setting up a secure work area, they decide to try a shortcut. Worker A will hold the far end of a 8.00 m work plank which weighs·U N and is secured with a hinge on the opposite end. Worker B will stand on the plank 4.11 m from worker A. Worker B also brings up his paint can, me 3.52 kg, which...
A young work crew is trying to quickly finish some touch-up painting to complete a job. Rather than setting up a secure work area, they decide to try a shortcut. Worker A will hold the far end of a 8.98 m work plank which weighs 114 N and is secured with a hinge on the opposite end. Worker B will stand on the plank 4.33 m from worker A. Worker B also brings up his paint can, mc = 3.52...
A young work crew is trying to quickly finish some touch‑up painting to complete a job. Rather than setting up a secure work area, they decide to try a shortcut. Worker A will hold the far end of a 8.00 m work plank which weighs 114 N and is secured with a hinge on the opposite end. Worker B will stand on the plank 4.99 m from worker A. Worker B also brings up his paint can, mc=3.58 kg, which...