A straight wire (length = 8.0 m) is bent to form a square. If the wire carries a current of 20 A, what is the magnitude of the magnetic field at the center of the square?
Simple Harmonic Motion: An object oscillates such that its position x as a function of time t obeys the equation x = (0.222 m) sin(314 s-1 t), where t is in seconds.(a) In one period, what total distance does the object move?(b) What is the frequency of the motion?(c) What is the position of the object when t = 1.00 s?
Potential of Point-Charges: A sphere with radius 2.0 mm carries a +2.0 μC charge. What is the potential difference, VB - VA, between point B, which is 4.0 m from the center of the sphere, and point A, which is 6.0 m from the center of the sphere? (k = 1/4πε0 = 9.0 × 109 N ∙ m2/C2)
A car travels around an unbanked highway curve (radius 0.15 km) at a constant speed of 25 m/s. What is the magnitude of the resultant force acting on the driver, who weighs 0.80 kN?
An 8000 kg satellite is launched from the surface of the earth, and injected into outer space a long distance from the earth. The initial velocity needed to launch the satellite into outer space is <img src="https://sciemce.com/files/4/3efb494c1b0711d98.png" class="w-image" /><img src="https://sciemce.com/files/4/4a7be7000cf22aa99.png" class="w-image" />
Addition by 1. Components: Two forces are acting on an object as shown in the figure. Assume that all the quantities shown are accurate to three significant figures.<img src="https://sciemce.com/files/4/ppg__cp1pbb0313192044__f15g1q25g1.jpg" alt="" style="vertical-align: 0.0px;" height="167" width="339" />(a) What is the magnitude of the resultant force on the object?(b) What is the direction of the resultant force?
A gas expands from an initial volume of 0.040 m3 and an initial pressure of 210 kPa to a final volume of 0.065 m3 while its temperature is kept constant. How much work is done by the system?
A ventilation fan with a moment of inertia of 0.034 kg·m2 has a net torque of 0.11 N·m applied to it. If it starts from rest, what angular momentum will it have 9.0 s later?
Moment of Inertia: In the figure, a weightlifter's barbell consists of two identical small but dense spherical weights, each of mass 50 kg. These weights are connected by a thin 0.96-m rod with a mass of 24 kg. Find the moment of inertia of the barbell through the axis perpendicular to the rod at its center, assuming the two weights are small enough to be treated as point masses.<img src="https://sciemce.com/files/4/ppg__cp1pbb0313192044__f98g1q6g1.jpg" alt="" style="vertical-align: 0.0px;" height="78" width="125" />
An urban legend has it that the RAF was testing the windshields of their aircraft for bird strikes using a chicken cannon given to them by the USAF. The windshields kept breaking because they were using frozen chickens instead of fresh ones. Using your knowledge of physics, you would reason that the legend is
The distance between the ruled lines on a grating is 1770 nm. The grating is illuminated at normal incidence with a parallel beam of white light in the 400 nm to 700 nm wavelength band
Calculate the average force a bumper would have to exert to bring a 1200-kg car to rest in 15 cm when the car had an initial speed of 2.0 m/s (about 4.5 mph)
A Carnot refrigerator has a coefficient of performance = 2.5. The refrigerator consumes 50 W of power. How much heat is removed from the interior of the refrigerator in 1 hour?
Calorimetry: An 920-g piece of iron at 100°C is dropped into a calorimeter of negligible heat capacity containing 50 g of ice at 0°C and 92 g of water, also at 0°C. What is the final temperature of the system? The specific heat of iron is 448 J/kg ∙ K, that of water is 4186 J/kg ∙ K, and the latent heat of fusion of water is 33.5 × 104 J/kg.
If R = 3.0 kΩ, C = 5.0 mF, ε = 6.0 V, Q = 15 mC, and I = 4.0 mA, what is the potential difference Vb−Va?<img src="https://sciemce.com/files/2/ppg__cognero__Chapter_29_Direct_Current_DC_Circuits.__media__6468346d-9e5f-43d3-add8-0ce49a3c23ff.PNG" style="vertical-align: 0px;" width="266px" height="52px" />
Microscopes are inherently limited by the wavelength of the light used. How much smaller (in order of magnitude) can we "see" using an electron microscope whose electrons have been accelerated through a potential difference of 50000 V than using red light (500 nm)?
Beats: The wavelengths of the sounds produced by two horns are 6.0 m and 7.0 m, respectively. What beat frequency is heard when the horns are sounded on a day when the speed of sound is 340 m/s?
Suppose that a car traveling to the west begins to slow down as it approaches a traffic light. Which of the following statements about its acceleration is correct?
A sports car and a moving van move at the same speed when they crash into a cement wall and stop equally quickly. The vehicle to have the greater force of impact will be
In a mass spectrometer, a singly-charged particle (charge e) has a speed of 1.0 × 106 m/s and enters a uniform magnetic field of 0.20 T. The radius of the circular orbit of the particle is 0.020 m
You hold an apple in one hand and an orange in the other. If you doubled the mass of the apple and tripled the mass of the orange, without changing the distance between them, the gravitational force between them would be
The objective lens of a microscope has a focal length of 2.4 mm and the eyepiece has an angular magnification of 15. The object is positioned 0.060 mm beyond the focal point of the objective
Two charges lie on the x axis, +3q at the origin, and −2q at x = 5.0 m. The point on the x axis where the electric potential has a zero value (when the value at infinity is also zero) is
A loop of wire (resistance = 2.0 mΩ) is positioned as shown with respect to a long wire which carries a current. If d = 1.0 cm, D = 6.0 cm, and L = 1.5 m, what current is induced in the loop at an instant when the current in the wire is increasing at a rate of 100 A/s?
A cylindrical capacitor is made of two thin-walled concentric cylinders. The inner cylinder has radius r1 = 4.0 mm, and the outer one a radius r2 = 8.0 mm. The common length of the cylinders is L = 150 m
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