Bissoy.com
Doctors Medicines MCQs Q&A

Below stated are some of the statements about the Alternating current. You need to identify which of the following is incorrect, 1. DC power is far more powerful than AC power. The efficiency and power to size characteristics of DC motors and apparatuses are increased. Lighting by DC (LED) is 75% more efficient than lighting from incandescence. 2. A comparatively high voltage alternating current may be generated and easily raised and dropped by the static equipment known as the transformer, which makes electrical energy transmission and distribution economical, 3. Initial costs and maintenance of the AC motor are less expensive since it has no switch and is less powerful than the DC motor for constant working speed, hence it is desired to create power as alternating current. 4. The great efficiency of transmission in ac makes electric power generation cost-effective, Produced in huge quantities in one station and distributed throughout a vast area.

Below stated are some of the statements about the Alternating current. You need to identify which of the following is incorrect, 1. DC power is far more powerful than AC power. The efficiency and power to size characteristics of DC motors and apparatuses are increased. Lighting by DC (LED) is 75% more efficient than lighting from incandescence. 2. A comparatively high voltage alternating current may be generated and easily raised and dropped by the static equipment known as the transformer, which makes electrical energy transmission and distribution economical, 3. Initial costs and maintenance of the AC motor are less expensive since it has no switch and is less powerful than the DC motor for constant working speed, hence it is desired to create power as alternating current. 4. The great efficiency of transmission in ac makes electric power generation cost-effective, Produced in huge quantities in one station and distributed throughout a vast area. Correct Answer Only 3

Concept: 

DC power is more energy-efficient than AC power.

DC Motors and appliance have higher efficiency and power to size characteristics.

DC-based lighting (LED) is as much as 75% more efficient than incandescent lighting.

→ A comparatively High Voltage alternating current may be generated and easily raised and dropped by static equipment such as Transformers, which makes electrical energy transmission and distribution economical.

→ The greater efficiency of transmission in AC makes electric power generation cost-effective produced in huge quantities in one station and distributed through vast areas.

Hence statements 1, 2 and 4 are correct.

∴ The incorrect statement is 3, So the correct option is option 2.

Related Questions

Following statements are given for DC motors (a) DC motors require less maintenance than AC motors (b) DC motors cannot provide high starting torque (c) DC motors are not suitable for very high-speed applications (d) The methods of speed control of DC motors are simpler and less expensive than those of AC motors Which of the following statements are correct?
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Modern civilization is completely dependent on energy, which has therefore to be abundant and also economical. About 85% of the world's energy is supplied by oil, coal and natural gas while nuclear, hydro, wind and solar power and biomass supply the rest. Coal, nuclear and hydro are used primarily to generate electricity while natural gas is widely used for heating. Biomass is used both for heating and cooking. The wind and solar power is the future's hope as they are sustainable energy sources. Oil powers almost all machines that move and that makes oil uniquely versatile. Oil powered airplanes carry 500 people across the widest oceans at nearly the speed of sound. Oil powered machines produce and transport food. Oil powered machines are ubiquitous. Clearly, we live in the age of oil but it is drawing to a close. According to data available if oil production remains constant until it's gone, there is enough to last 42 years. Oil wells will produce less as they become depleted, which will make it impossible to keep production constant. Similarly natural gas and coal will last another 61 years and 133 years respectively. Naturally, as they become scarce, they become expensive, leading to a worldwide energy crisis. If we are to survive on this planet, we have to make a transition to sustainable energy sources. The transition may be willy-nilly or planned - the choice is ours. The dawning era of limited and expensive energy will be very difficult for everyone on earth but will be even more difficult if it is not anticipated. It is of utmost importance that the public and policymakers understand the global energy crisis and act in tandem to ensure that the species 'homo sapiens' does not become extinct. Biomass is an energy source used in
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Modern civilisation is completely dependent on energy, which has therefore to be abundant and also economical. About 85% of the world's energy is supplied by oil, coal and natural gas while nuclear, hydro, wind and solar power and biomass supply the rest. Coal, nuclear and hydro are used primarily to generate electricity while natural gas is widely used for heating. Biomass is used both for heating and cooking. The wind and solar power is the future's hope as they are sustainable energy sources. Oil powers almost all machines that move and that makes oil uniquely versatile. Oil powered airplanes carry 500 people across the widest oceans at nearly the speed of sound. Oil powered machines produce and transport food. Oil powered machines are ubiquitous. Clearly, we live in the age of oil but it is drawing to a close. According to data available if oil production remains constant until it's gone, there is enough to last 42 years. Oil wells will produce less as they become depleted, which will make it impossible to keep production constant. Similarly natural gas and coal will last another 61 years and 133 years respectively. Naturally, as they become scarce, they become expensive, leading to a worldwide energy crisis. If we are to survive on this planet, we have to make a transition to sustainable energy sources. The transition may be willy-nilly or planned - the choice is ours. The dawning era of limited and expensive energy will be very difficult for everyone on earth but will be even more difficult if it is not anticipated. It is of utmost importance that the public and policymakers understand the global energy crisis and act in tandem to ensure that the species 'homo sapiens' does not become extinct. The energy sources of the future are
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Modern civilization is completely dependent on energy, which has therefore to be abundant and also economical. About 85% of the world's energy is supplied by oil, coal and natural gas while nuclear, hydro, wind and solar power and biomass supply the rest. Coal, nuclear and hydro are used primarily to generate electricity while natural gas is widely used for heating. Biomass is used both for heating and cooking. The wind and solar power is the future's hope as they are sustainable energy sources. Oil powers almost all machines that move and that makes oil uniquely versatile. Oil powered airplanes carry 500 people across the widest oceans at nearly the speed of sound. Oil powered machines produce and transport food. Oil powered machines are ubiquitous. Clearly, we live in the age of oil but it is drawing to a close. According to data available if oil production remains constant until it's gone, there is enough to last 42 years. Oil wells will produce less as they become depleted, which will make it impossible to keep production constant. Similarly natural gas and coal will last another 61 years and 133 years respectively. Naturally, as they become scarce, they become expensive, leading to a worldwide energy crisis. If we are to survive on this planet, we have to make a transition to sustainable energy sources. The transition may be willy-nilly or planned - the choice is ours. The dawning era of limited and expensive energy will be very difficult for everyone on earth but will be even more difficult if it is not anticipated. It is of utmost importance that the public and policymakers understand the global energy crisis and act in tandem to ensure that the species 'homo sapiens' does not become extinct. The theme of the passage is
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Modern civilisation is completely dependent on energy, which has therefore to be abundant and also economical. About 85% of the world's energy is supplied by oil, coal and natural gas while nuclear, hydro, wind and solar power and biomass supply the rest. Coal, nuclear and hydro are used primarily to generate electricity while natural gas is widely used for heating. Biomass is used both for heating and cooking. The wind and solar power is the future's hope as they are sustainable energy sources. Oil powers almost all machines that move and that makes oil uniquely versatile. Oil powered airplanes carry 500 people across the widest oceans at nearly the speed of sound. Oil powered machines produce and transport food. Oil powered machines are ubiquitous. Clearly, we live in the age of oil but it is drawing to a close. According to data available if oil production remains constant until it's gone, there is enough to last 42 years. Oil wells will produce less as they become depleted, which will make it impossible to keep production constant. Similarly natural gas and coal will last another 61 years and 133 years respectively. Naturally, as they become scarce, they become expensive, leading to a worldwide energy crisis. If we are to survive on this planet, we have to make a transition to sustainable energy sources. The transition may be willy-nilly or planned - the choice is ours. The dawning era of limited and expensive energy will be very difficult for everyone on earth but will be even more difficult if it is not anticipated. It is of utmost importance that the public and policymakers understand the global energy crisis and act in tandem to ensure that the species 'homo sapiens' does not become extinct. The synonym for Ubiquitous is
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Modern civilisation is completely dependent on energy, which has therefore to be abundant and also economical. About 85% of the world's energy is supplied by oil, coal and natural gas while nuclear, hydro, wind and solar power and biomass supply the rest. Coal, nuclear and hydro are used primarily to generate electricity while natural gas is widely used for heating. Biomass is used both for heating and cooking. The wind and solar power is the future's hope as they are sustainable energy sources. Oil powers almost all machines that move and that makes oil uniquely versatile. Oil powered airplanes carry 500 people across the widest oceans at nearly the speed of sound. Oil powered machines produce and transport food. Oil powered machines are ubiquitous. Clearly, we live in the age of oil but it is drawing to a close. According to data available if oil production remains constant until it's gone, there is enough to last 42 years. Oil wells will produce less as they become depleted, which will make it impossible to keep production constant. Similarly natural gas and coal will last another 61 years and 133 years respectively. Naturally, as they become scarce, they become expensive, leading to a worldwide energy crisis. If we are to survive on this planet, we have to make a transition to sustainable energy sources. The transition may be willy-nilly or planned - the choice is ours. The dawning era of limited and expensive energy will be very difficult for everyone on earth but will be even more difficult if it is not anticipated. It is of utmost importance that the public and policymakers understand the global energy crisis and act in tandem to ensure that the species 'homo sapiens' does not become extinct. The survival of mankind will depend on
Consider the following statements regarding ac drives: 1. For the same kW rating, ac motors are 20% to 40% light weight as compared to dc motors. 2. The ac motors are more expensive as compared to same kW rating dc motors. 3. The ac motors have low maintenance as compared to dc motors. Which of the above statements are correct?
A, B, C, D, K, L, M and O are researchers and are working in three different institutes, X, Y and Z. They are working in three different areas namely, solar energy, sustainable development, and rainwater harvesting for agricultural purpose. Not less than two or more than three researchers are working in the same area and not more than three of them are working the same institute. K is researching in the sustainable development in the institute Y with B who is doing research in rainwater harvesting. A and M are doing research in the same area but not in sustainable development and are not working in the institute Y. C is researching in solar energy in the institute Z, only with D who is working in sustainable development. L is researching in rainwater harvesting area and not working in the institute where A works. O is not doing research in the solar energy. Choose option for answering question, In which of the institute/institutes at least one researcher is working in the area of solar energy ?
There is only one rail track between stations A and B on a railway line. One hour after the northbound superfast train N leaves station A for station B, the southbound passenger train S reaches station A from station B. The speed of superfast train is twice that of express train E, while the speed of passenger train S is half of that of train E. On some one day train N leaves from station A to station B 20 minutes late than its usual schedule. Both Train N and Train S have increased their speed to maintain the schedule as per the table. If the superfast train doubles its speed, then what should be the ratio (approximately) of the speed of the passenger train to the speed of the superfast train so that the passenger train reaches the station on that day at the exact scheduled time.
In the following question, sentences of a paragraph have been jumbled and labelled as A, B, C and D. You are required to rearrange the jumbled sentences of the paragraph and mark your response accordingly by selecting the correct option. A: Transformers can also be used for isolation, where the voltage in equals the voltage out, with separate coils not electrically bonded to one another. B: Transformers are most commonly used for increasing low AC voltages at high current (a step-up transformer) or decreasing high AC voltages at low current (a step-down transformer) in electric power applications. C: It was discovered in 1831. D: A transformer is a passive electrical device that transfers electrical energy from one electrical circuit to another.