A cybertruck lifts a 575 lb weight using the pulley system shown. The pulley is h = 18.5 ft high and the cybertruck started from rest at point A and has traveled sc = 30 ft. Note: This problem must be solved using absolute dependent motion (Hibbeler text section 12.9) a) If the cybertruck has a constant acceleration of ac = 22 ft/s2, how fast would it be moving? vc = ft/s b) How fast would the weight be moving (please report speed as a positive number)? vw = ft/s c) What is the magnitude of acceleration of the weight? aw = ft/s2 d) If the cybertruck stopped accelerating at this instant, the weight would be... Traveling at a constant speed Speeding up Slowing down
The 100−lb block is stationary at time t = 0, and then it is subjected to the force P shown. Note that the force is zero for all times beyond t = 20 sec. If μs = 0.6, μk = 0.4, and θ = 25∘, determine the velocity v of the block at time t = 25 sec. Also, calculate the time t at which the block comes to rest again. (v = 89.4 ft/sec, the block never stops)
Two tiny metal spheres A and B of mass mA = 5.21 g and mB = 11.1 g have equal positive charges q = 4.55 μC. The spheres are connected by a massless nonconducting string of length d = 0.864 m, which is much greater than the radii of the spheres. (a) What is the electric potential energy of the system? Suppose you cut the string. At that instant, what is the acceleration of (b) sphere A and (c) sphere B? A long time after you cut the string, what is the speed (d) sphere A and (e) sphere B? (a) Number Units (b) Number Units (c) Number Units (d) Number Units (e) Number Units
The length of a simple pendulum is 0.85 m and the mass of the particle (the "bob") at the end of the cable is 0.22 kg. The pendulum is pulled away from its equilibrium position by an angle of 8.1∘ and released from rest. Assume that friction can be neglected and that the resulting oscillatory motion is simple harmonic motion. (a) What is the angular frequency of the motion? (b) Using the position of the bob at its lowest point as the reference level, determine the total mechanical energy of the pendulum as it swings back and forth. (c) What is the bob's speed as it passes through the lowest point of the swing? (a) Number Units (b) Number Units (c) Number Units
A proton with initial kinetic energy 33.83 eV is incident on a potential barrier of thickness 5.000×10−12 m and height 45.00 eV. The mass of a proton is m = 1.673×10−27 kg, and Planck's reduced constant is ℏ = 1.055×10−34 J⋅s. Find the probability P that the proton tunnels through the barrier. P = %
A charge +q is suspended at the center of a hollow, electrically neutral, spherical, metallic conductor, as Figure 18.30 illustrates. The table shows a number of possibilities for the charges that this suspended charge induces on the interior and exterior surfaces of the conductor. Which one of the possibilities is correct? FIGURE 18.30 A positive charge +q is suspended at the center of a hollow spherical conductor that is electrically neutral. Induced charges appear on the inner and outer surfaces of the conductor. The electric field within the conductor itself is zero.
A rocket of mass 3.02×105 kg is in flight near earth's surface. Its thrust is directed at an angle of 55.9∘ above the horizontal and has a magnitude of 7.27×106 N. Find the (a) magnitude and (b) direction of the rocket's acceleration. Give the direction as an angle above the horizontal. (a) Number Units (b) Number Units
A semi-circular track A of radius R is at rest on the horizontal plane, where A is adjacent to block B. A small block C is released from the top position of the curved surface of A, as shown in the figure. The initial height of block C is h above the horizontal plane. Assume that objects A, B, and C have the same mass m and all surfaces are smooth, solve the following problems. (a) Find the speed of B when A and B just separate. (10 marks) (b) Find the maximum height that C can reach. Your measurement should be made from the horizontal plane. (10 marks)
A man is driving his car with speed 46.0 mi/h on a horizontal stretch of road. (a) When the road is wet, the coefficient of static friction between the road and the tires is 0.105. Find the minimum stopping distance (in m). m (b) When the road is dry, μs = 0.602. Find the minimum stopping distance (in m). m
A hawk flies in a horizontal arc of radius 10.3 m at a constant speed 3.35 m/s. (a) Find its centripetal acceleration. m/s2 (b) It continues to fly along the same horizontal arc, but increases its speed at the rate of 1.15 m/s2. Find the acceleration in this situation at the moment the hawk's speed is 3.35 m/s. magnitude m/s2 direction - from the direction of velocity towards center of the circle
A man is pulling two boxes, one on top of the other, up the ramp shown by pulling on a rope parallel to the surface of the ramp. The coefficient of kinetic friction between the ramp and the lower box is 0.444, and the coefficient of static friction between the two boxes is 0.800. With what force does the man have to pull in order to move the boxes up the ramp at a constant speed of 15.0 cm/s? [Assume the static friction between the two boxes is sufficient to prevent the top box from slipping. You may check this, if you wish.
Radiotherapy devices often utilize linear particle accelerators that require a high voltage pulse. A Marx generator is a circuit that allows the input voltage to be multiplied and delivered to a load i a short period of time. In the circuit shown in the figure, a fixed voltage source is applied between points a and b, and the capacitors are charged in parallel with all four switches open. (a) What is the final charge (in mC) on each of the capacitors when the voltage source is applied across points a and b and all four 5 witches are open? Q1 = mc Q2 = mc Q3 = mc (b) How long does it take for each of the capacitors to reach 99.0% of their maximum charge? t1 = ms t2 = ms t3 = ms (d) What is the initial voltage (in V) across points c and d immediately after all four switches are closed? (e) What is the time interval (in ms) required for the current in the circuit to reach 20.0% of its initial value after all four switches are closed? ms
The electric potential V in the space between two flat parallel plates 1 and 2 is given (in volts) by V = 1200x2, where x (in meters) is the perpendicular distance from plate 1. At x = 1.5 cm, (a) what is the magnitude of the electric field and (b) is the field directed toward or away from plate 1? (a) N/C (b)
In the figure point P is at a distance d1 = 2.72 m from particle 1(q1 = −5e) and distance d2 = 1.26 m from particle 2(q2 = +5e), with both particles fixed in place. (a) With V = 0 at infinity, what is V at P? If we bring a particle of charge q3 = +5e from infinity to P, (b) how much work do we do and (c) what is the potential energy of the three-particle system? (a) Number Units (b) Number Units (c) Number Units
The momentum of an object and its change in momentum during a time interval are shown below. p→i Δp→ Move the Δp→ arrow below as needed, then move the p→f arrow such that it represents the momentum of the object at the end of the time interval. Note that the three vectors are actually co-linear, but the arrows below are at different heights so that they can be viewed without any overlapping. The dotted segments are guides for aligning the ends of the arrows.
43. (II) The roller-coaster car shown in Fig. 6-41 is dragged up to point 1 where it is released from rest. Assuming no friction, calculate the speed at points 2, 3, and 4. FIGURE 6-41 Problems 43 and 53.
It turns out that the Earth is actually flat. Our flat Earth is well approximated by a disk of radius R = 6378 km and total mass m = 5.972×1024 kg, uniformly distributed across the disk. Assume that "Earth" is held fixed at the origin of an inertial coordinate frame such that it lies in the x-y plane. A 100 kg spacecraft is dropped from an initial z position of z0 = 10, 000 km above the exact centerline of the Earth (x0 = y0 = 0 km), as shown in the figure below Determine: The acceleration vector of the spacecraft at the moment it is dropped. The velocity vector of the spacecraft when it is at a distance of 1, 000 km above the Earth's surface. Since both quantities are vectors, you must justify both their magnitudes and directions. Assume G = 6.67×10−11 Nm2/kg2