TMA3/PHY102

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My TMA Home TMA Results My Pending TMA Quick Help My TMATMA InstructionCourse DetailTMA CalendarGrading Message BoardQuick InfoInstructor Message Quiz NoteQuiz Tip - 1Quix Tip - 2 TMA Quiz Questions TMA: TMA3/PHY102 Matric Number: SCORE=10.00 PHY102 - Electricity, Magnetism and Modern Physics Mr. Ibanga Efiong (eibanga@noun.edu.ng ) 1 In the circuit shown, each of the cells has an emf of 2V and internal resistance of 0:1Ω$$0.1\mathrm{\Omega }$$ . Find the current in through the 0.5Ω$$\mathrm{}\mathrm{}$$ Click here to see exhibit 0.13A 3.45A 1.27A 2.44A 2 Calculate the electric field everywhere outside of a very long rod, radius R and charged to a uniform linear charge density λ$$$$ . E⃗ =λπrϵ0r^$$\stackrel{}{}\frac{}{{}_{\mathrm{}}}\stackrel{}{}$$ E⃗ =λπϵ0ln1rr^$$\stackrel{}{}\frac{}{{}_{\mathrm{}}}\frac{\mathrm{}}{}\stackrel{}{}$$ E⃗ =λ2πrϵ0r^$$\stackrel{}{}\frac{}{\mathrm{}{}_{\mathrm{}}}\stackrel{}{}$$ E⃗ =λ2πϵ0ln1rr^$$\stackrel{}{}\frac{}{\mathrm{}{}_{\mathrm{}}}\frac{\mathrm{}}{}\stackrel{}{}$$ 3 Kirchhof's junction rule is statement of conservation of ----------- mass energy charge momentum 4 A galvanometer of resistance 120Ω$$\mathrm{}\mathrm{}$$ a full scale deflection with a current of 0.0005A. How would you convert it to an ammeter that reads a maximum current of 5A? connect 2000Ω$$\mathrm{}\mathrm{}$$ in parallel to it connect 200.12Ω$$\mathrm{}\mathrm{}$$ in series to it connect $20.10\Omega$$ in series to it connect 0.012Ω$$\mathrm{}\mathrm{}$$ in parallel to it 5 A galvanometer with coil resistance 12.0Ω$$\mathrm{}\mathrm{}$$ shows full scale deflection for a current of 2.5mA. How would you convert it into a voltmeter of range 0 to 10.0V? 3988Ω$$\mathrm{}\mathrm{}$$ in series 0.43Ω$$\mathrm{}\mathrm{}$$ in parallel Ω$$\mathrm{}$$ in parallel 1.62Ω$$\mathrm{}\mathrm{}$$ in series 6 A series circuit consisting of an uncharged 42ÖF capacitor and 10MΩ$$\mathrm{}\mathrm{}$$ resistor is connected to 100V power source. What are the current in the circuit and the charge on the capacitor after one time constant? 3.7μA$$\mathrm{}$$ and 126μC$$\mathrm{}$$ 4.6μA$$\mathrm{}$$ and 221μC$$\mathrm{}$$ 7.2μA$$\mathrm{}$$ and 100μC$$\mathrm{}$$ 1.3μA$$\mathrm{}$$ and 52μC$$\mathrm{}$$ 7 A capacitor of 2.0μF$$\mathrm{}$$ is connected to a battery of 2.0V through a resistance of 10kΩ$$\mathrm{}\mathrm{}$$ . What is the initial current in the circuit and the current after 0.02s? 0.5μA$$\mathrm{}$$ and 0.074mA 7.4A and 5.0mA 0.2μA$$\mathrm{}$$ and 0.074mA 6.2μA$$\mathrm{}$$ and 7.04mA 8 A conductor 2cm long carrying a current of 8A lies at right angles to a magnetic field of which the flux density is 1.0T. Calculate the force exerted on the conductor 0.20N 0.16N 0.25N 0.45N 9 One end of a simple rectangular wire-loop current balance is inserted into a solenoid. A force of 3.0×10−3$$\mathrm{}{\mathrm{}}^{\mathrm{}}$$ N is found to act on this end when a current of 2.0A is flowing in it. If the length of the conductor forming the end of the the wire-loop is 0. 0.043T 0.26T 0.43T  0.015T 10 A staight wire 1.0m long carries a currernt of 100A at right-angles to a uniform magnetic field of 1.0T. Find the mechanical force on the wire and the power required to move it at 15m/s in a plane at right-angles to the field. 100N and 1.5kW  200N and 2.5kW 300N and 1.4kW 200N and 2.7kW 11 A rectangular coil of dimensions 20cm by 15cm lies with its plane parallel to a magnetic field of 0.5W/$m2$$\mathrm{}{}^{\mathrm{}}$$ . The coil, carrying a current of 10A experiences a torque of 4.5Nm in the field. How many loops has the coil? 100 60 30 20 12 An electric feild of 50kV/m is perpendicular to a magnetic field 0.25T. What is the velocity of a charge whose initial of motion is perpendicular to both fields and which passes through the fields undeflected? 3×103$$\mathrm{}{\mathrm{}}^{\mathrm{}}$$ m/s 2×105$$\mathrm{}{\mathrm{}}^{\mathrm{}}$$ m/s 4×107$$\mathrm{}{\mathrm{}}^{\mathrm{}}$$ m/s 5×104$$\mathrm{}{\mathrm{}}^{\mathrm{}}$$ m/s 13 A proton is accelerated through a potential difference of 100V and the enters a region in which it is moving perpendicular to a magnetic field of flux density 0.20T. Find the radius of the circular path in which it will travel. 0.9km o.7km 0.3km 0.5km 14 An electron enters a uniform magnetic field 0.20T at an angle of 30o$${\mathrm{}}^{}$$ the field. Determine the pitch of the helical path assuming its speed is 3×107$$\mathrm{}{\mathrm{}}^{\mathrm{}}$$ m/s 90.6m 37.8m 56.1m 46.5m 15 A positive ion passes through an electric and magnetic fields which are mutually perpendicular. The electric field strength is 20.0kV/m while the magnetic flux density is 0.40T. At what speed will the ion pass through undeflected? 6.0×104$$\mathrm{}{\mathrm{}}^{\mathrm{}}$$ m/s 5.0×104$$\mathrm{}{\mathrm{}}^{\mathrm{}}$$ m/s 7.0×104$$\mathrm{}{\mathrm{}}^{\mathrm{}}$$ m/s $8.0\times10^{4}$$m/s 16 For how long must a steady current of 2A flow through a copper voltameter to deposit 10À3kg of copper? Z for coper is 0.000329g/C 42.1min 22.6min 30.2min 25.3min 17 An ammeter is suspeted of giving inaccurate readings. In order to confirm the readings, the ammeter is connected to a silver votltameter in series and a steady current is passed for one hour. The ammeter reads 0.56A and 2.0124g of silver is deposited. Wha 0.06A 0.11A 1.1A 6.0A 18 The magnetic flux through each loop of a 35-loop coil is given by (3:6tÀ0:71t3)Â10À2Tm2, where the time is in seconds. Determine the induced emf at t=5.0s. 6.17V 14.43V 17.49V 9.17V 19 A single turn coil of cross-sectional area 7.2cm^2 is in the a magnetic field of flux desity 0.45T. The field which is perpendicular to the coil, is steadily reduced to 0.0T in 5s. Calculate the induced emf. 0:72ÖV 0:52ÖV 0:47ÖV 0:65ÖV 20 What is the self - inductance of an air-core solenoid, 1m long and 0.05m in diameter, if it has 1400 turns? 5.23mH 4.84mH 3.63mH 2.42mH