OC userin Physics·5 Jun 201849. For each solution, calculate the initial and final pH after adding 0.010 mol of HCl. a. 500.0 mL of pure water b. 500.0 mL of a buffer solution that is 0.125 Min HC2H302 and 0.115 Min NaC H302 c. 500.0 mL of a buffer solution that is 0.155 M in C2H5NH2 and 0.145 M in C2H5NH3CI
OC userin Physics·4 Jun 201825.31. In the circuit shown in Fig. E25.30, the 16.0-V battery is removed and reinserted with the opposite polarity, so that its negative terminal is now next to point a. Find (a) the current in the circuit (magnitude and direction); (b) the terminal voltage Va of the 16.0-V battery; (c) the potential difference Vas of point a with respect to point c. (d) Graph the potential rises and drops in this circuit (see Fig. 25.20).
OC userin Physics·4 Jun 2018A toy car is held at rest against a compressed spring, as shown in the figure. When released, the car slides across the room. Let be the initial position of the car. Assume that friction is negligible.
OC userin Physics·4 Jun 201814.7. A 2.40-kg ball is attached to an unknown spring and allowed to oscillate. Figure E14.7 shows a graph of the ball's position x as a function of time t. What are the oscillation's (a) period, (b) frequency, ©) angular frequency, and (d) amplitude? (e) What is the force constant of the spring? Figure E14.7 x (cm) 0.50 930
OC userin Physics·2 Jun 201825.15 . A cylindrical tungsten filament 15.0 cm long with a diameter of 1.00 mm is to be used in a machine for which the tem- perature will range from room temperature (20°C) up to 120°C. It will carry a current of 12.5 A at all temperatures (consult Tables 25.1 and 25.2), (a) What will be the maximum electric field in this filament, and (b) what will be its resistance with that field? (c) What will be the maximum potential drop over the full length of the filament?
OC userin Physics·31 May 20183) [8 pts) A 12.0 kg box slides 4.00 m down a frictionless ramp as shown below, then collides with a spring whose spring constant is 500. N/m. a. What is the maximum compression of the spring? b. At what compression of the spring does the box have its maximum speed (Hint: find the position where the force on the box is zero)? c. What is the initial acceleration of the box when it starts back up the ramp after maximum compression? 4.0 m 30
OC userin Physics·1 Jun 2018Pull 33.0 11.65 . A worker wants to figure P11.65 turn over a uniform, 1250-N, 2.20 m rectangular crate by pulling at 53.0° on one of its verti- 1.50 m cal sides (Fig. P11.65). The floor is rough enough to pre- vent the crate from slipping. (a) What pull is needed to just start the crate to tip? (b) How hard does the floor push upward on the crate? (c) Find the friction force on the crate. (d) What is the minimum coefficient of static friction needed to prevent the crate from slipping on the floor?
OC userin Physics·30 May 2018The surface temperature of the photosphere of the Sun isapproximately 5000K. Yet the maximum temperature achieved by a flatsolar thermal collector is only about400K. Why?
OC userin Physics·29 May 20181) [8 pts) A bullet (mass: 5.00 grams) moving with an initial speed of 400. m/s is fired into, and passes through, a block whose mass is 1.0 kg, as shown in the diagram. The block, initially at rest on a flat and frictionless surface, is connected to a spring with a spring constant of k=900. N/m. After the collision, the block moves 5.00 cm to the right before starting to rebound. a. What is the speed at which the bullet emerges from the block? b. What is the mechanical energy lost in the collision? bullet mm before collision after collision
OC userin Physics·28 May 201830. If an electrolytic cell contains a mixture of species that can be oxidized, how do you determine which species will actually be oxidized? If it contains a mixture of species that can be reduced, how do you determine which one will actually be reduced?
OC userin Physics·29 May 20182.17. CALC A car's velocity as a function of time is given by 0.(t) - a+ Br?, where a - 3.00 m/s and B- 0.100 m/s. (a) Calculate the average acceleration for the time interval - 0 tot -5.00 s. (b) Calculate the instantaneous acceleration for 1-0 and 1-5.00 s. (c) Draw Url and a graphs for the car's motion between t- and/-5.00 s.
OC userin Physics·27 May 20189.20 - Compact Disc. A compact disc (CD) stores music in a coded pattern of tiny pits 10'm deep. The pits are arranged in a track that spirals outward toward the rim of the disc; the inner and outer radii of this spiral are 25.0 mm and 58.0 mm, respectively, As the disc spins inside a CD player, the track is scanned at a constant linear speed of 1.25 m/s. (a) What is the angular speed of the CD when the innermost part of the track is scanned? The outermost part of the track? (b) The maximum playing time of a CD is 74.0 min. What would be the length of the track on such a maximum-duration CD if it were stretched out in a straight line? (c) What is the average angular acceleration of a maximum- duration CD during its 74.0-min playing time? Take the direction of rotation of the disc to be positive.
OC userin Physics·29 May 201814.71 ... An apple weighs 1.00 N. When you hang it from the end of a long spring of force constant 1.50 N/m and negligible mass, it bounces up and down in SHM. If you stop the bouncing and let the apple swing from side to side through a small angle, the frequency of this simple pendulum is half the bounce frequency. (Because the angle is small, the back-and-forth swings do not cause any appreciable change in the length of the spring.) What is the unstretched length of the spring (with the apple removed)?
OC userin Physics·28 May 201824.5. A 10.0-4.F parallel-plate capacitor with circular plates is connected to a 12.0-V battery. (a) What is the charge on each plate? (b) How much charge would be on the plates if their separa- tion were doubled while the capacitor remained connected to the battery? (c) How much charge would be on the plates if the capaci- tor were connected to the 12.0-V battery after the radius of each plate was doubled without changing their separation?
OC userin Physics·28 May 20185.51 In another version of the Figure E5.51 "Giant Swing" (see Exercise 5.50), the seat is connected to two ca- bles, one of which is horizontal (Fig. E5.51). The seat swings in 40.0° a horizontal circle at a rate of 28.0 rpm (rev/min). If the seat weighs 255 N and an 825-N per- son is sitting in it, find the ten 17.50 m sion in each cable.