28/03/2020 Current Electricity and Electrical Quantities(Senior Class Physics Study by Topics) 28/03/2020 0Comments by Gate Academy Welcome to your Current Electricity and Electrical Quantities(Senior Class Physics Study by Topics) NAME EMAIL PHONE NUMBER 1. A ____ ____ is related to the force that causes electric charges to flow. Voltage difference Electric currents Current flow Dry cell batteries 2. A wire of uniform cross-sectional area has a resistance R. The wire is stretched until its length increases by 10%. By assuming that the new wire has the same volume as before, the resistance of the new wire is 1.0 R 1.1 R 0.9 R 1.2 R 3. A battery is connected in series with a resistor R. The battery transfers 2000 C of charge completely round the circuit. During this process, 2500J of energy is dissipated in the resistor R and 1500J is dissipated in the battery. The e.m.f of the battery is 0.50 V 1.25 V 2.00 V 0.75 V 4. If R1 and R2 are the filament resistances of 200 watt and a 100 watt bulb respectively, both designed to run at the same voltage, then R2 is four times R1 R1 is four times R2 R1 is two times 3R2 R2 is two times R1 5. In a parallel circuit the component with the largest resistance gets:- The most potential difference The most current All components get the same current The least current 6. Voltage is a measurement of what? Potential energy stored in a battery Radiant energy of a lightbulb in a circuit The flow of electrons Kinectic energy of a motor in a circuit 7. A toaster operating at 240V has a resistance of 120Ω. The power is 480 W 2 W 240 W 400 W 8. As the current through a filament light bulb, its resistance increases. The best reason for this is:- The current increases The potential difference increases The light gets brighter The filament gets hotter 9. Receiving an electric shock from a doorknob is an example of ____________. Current electricity Spontaneous electricity Static electricity 10. Six wet cells made up of lead and lead dioxide plates in a sulfuric acid solution. Wet cell batteries Resistance Terminal batteries Lead-Acid batteries 11. What is the unit for current? Volts Amperes Joules Ohms 12. According to Faraday's law of electrolysis, when a current is passed, the mass of ions deposited at the cathode is independent of Current Charge Resistance Time 13. What is the unit for energy? Joules Amperes Ohms Volts 14. What happens to two terminals of a dry-cell battery connected in a circuit involving zinc and several chemicals in the paste The chemical reaction in each cell provides a voltage difference Electrons are transferred between some of the compounds in this chemical reaction Protons are transferred between some of the compounds in this chemical reaction. Neutrons are transferred between some of the compounds in this chemical reaction. 15. Why can birds sit on a power line? Because birds' feet are insulated so current is not conducted through them Because the wire is in the air and air has infinite resistance so no current flows through the wire Because birds have minimal resistance compared to household electronics, so current is diverted to the houses instead Because both feet are on the same voltage line, so there is no potential difference, so current does not flow through the bird 16. A way to measure the resistance of objects and materials Electric current Simple circuit Voltage difference Ohms Law 17. A __________ is a closed path or loop around which an electric current flows. Current electricity Battery Electron Circuit 18. What ultimately happens to the cow in this situation? During a thunderstorm, if lightning hits the ground near a cow, then the current starts to spread out in the groud. Since the ground is wet, it is easier to spread horizontally, and also, the ground is somewhat positively charged. When the current starts to spread while a cow is eating grass, the current flows from the cow's mouth (A), goes through its leg (B) and goes back to the ground. The current will flow until the voltage becomes zero. Because cow's hind leg (D) has lower potential energy than its front leg (C), the current can flow through the cow. The cow becomes a part of the electric circuit. The cow feels a slight tingle but continues eating. All the current builds up in the cow's bell which will shock the rancher later. The cow gets a big electric shock and probably dies Nothing happens to the cow. 19. If the length of a copper wire has a certain resistance R, then on doubling the length its specific resistance Will remain the same Will be doubled Will become 1/4 th Will become 4 times 20. A typical size-D battery has about how many volts? 0.05 V 100 V 1.5 V 9 V 21. The SI unit for charge is in Ampere Joules Current Coulomb 22. Charge of 60 C passes through an electric lamp in 2 minutes. Then the current in the lamp is 30 A 1 A 0.5 A 5A 23. A 100 W bulb B1 and two 60 W bulb B2 and B3 are connected to a 250V source as shown in the Figure. Now W1, W2 and W3 are the output powers of the bulbs B1, B2 and B3 respectively. Then W1 < W2 < W3 W1 > W2 = W3 W1 < W2 = W3 W1 > W2 = W3 24. When you attach a battery to an electric light bulb, what process makes the bulb light up? Protons flowing from the battery into the bulb Chemicals moving from the battery through the wire Electrons flowing through the circuit 25. What should you never bring near an electric appliance? Water Plastic Wind 1 out of 25 Time is Up! Time's up
