Skip to main content

CBSE PHYSICS: X Magnetic effect of current CBSE Test paper solved

Image
By
                               CBSE TEST PAPER -2012-13
 Time: 1hr.  CHAPTER: MAGNETIC EFFECT OF CURRENT        FM: 30
1. A positively charged particle (alpha-particle) projected towards west is deflected towards north by magnetic field. The direction of magnetic field is          
(a) towards south (b) towards east (c) downward (d) upward.
2. A rectangular coil of copper wires is rotated in a magnetic field. The direction of the induced current changes once in each   
(a) two revolutions (b) one revolution (c) half revolution (d) one-fourth revolution.
3. Permanent magnets are made up of
(a) Alnico     (b) soft iron  (c) copper (d) aluminum.                            
4. Which of the following properties of a proton can change when it moves freely in a magnetic field
(a) Mass              (b) speed              (c) velocity           (d) momentum
5. The direction of the magnetic field at a point P above the wire carrying current is
(a) Down the page (b) up the page  (c) into the page   (d) out of the page
6. An alternating current has frequency of 50 Hz. How many times does it change its direction in one second?
7 . What is the advantage of the third wire of earth connection in domestic appliances?
8.  What is the S.I. unit of magnetic flux ?
Ans:  Weber : The magnetic flux linked with a surface is defined as the number of magnetic field lines passing normally through that surface.
9 . How can we increase the speed of a D.C. motor?
10. Why do not two magnetic field lines intersect each other?
11. What is a solenoid? Draw magnetic field lines showing the magnetic field inside and outside the current carrying solenoid?
12. (a) What is short circuiting? (b) What is overloading? How can you avoid overloading?
13. What are the ways to detect the polarity of a current carrying solenoid?
14. Consider a circular loop of wire lying in the plane of the table. let the current pass through the loop clockwise. Apply the right hand rule to find out the direction of magnetic field inside and outside the loop?
15. What is the orientation of a current caring conductor relative to the direction of magnetic field for
(a) Maximum magnetic force.              (b) Minimum magnetic force
   For Online Help Log to www.jsuniltutorial.weeebly.com
                     CBSE TEST PAPER -2012-13 Answers
 Time: 1hr.  CHAPTER: MAGNETIC EFFECT OF CURRENT             FM: 30
1.  Ans. (a) Toward south.
2. (c) half revolution
3.(a) Alnico     (b) soft iron  (c) copper (d) aluminum.                            
4.(c) velocity             
5.(d) out of the page
6. Ans.  As the frequency is 50 Hz, so a.c. completes 50 cycles in 1 second. In other words, it reverses its direction 100 times in one second.
7.Ans: Earth wire is connected to the metallic case of an electrical appliance to  protect from electric shock by transferring excess amount of current to the earth.
8. Ans:  Weber : The magnetic flux linked with a surface is defined as the number of magnetic field lines passing normally through that surface.
9 .  Ans. We can increase the speed of rotation of a D.C.  motor by increasing
(i) area of the coil   (ii) number of turns in the coil   (iii) magnetic field and (iv) current.
10.  Ans: The two magnetic field lines never intersect each other because at the point of intersection there will be two directions of magnetic field, which is not possible
11.  Ans: A coil of many turns of insulated copper wire closely wound in the shape of a ring is known as a solenoid.
12.  Ans(a) when live wire and the neutral wires come in contact with each other resistance of the circuit becomes very small and huge amount of current flows and produces large heat which can cause fire. This phenomenon is called short circuiting
(b). If  many electrical appliances of high power ratings are connected in a single socket large amount of current  starts flowing in the circuit. This phenomenon is called overloading.
It can be avoided by the following methods
(i) Not use too many appliance is a single socket
(ii) To apply preventive methods of short circuiting.

13. Ans: If the current in the coil facing you is flowing in clockwise direction then its the south pole. If the current is flowing in anti clockwise direction, then its the north pole.
14. Ans: Inside the loop, direction of the magnetic field lines are into the table.
Outside the loop the magnetic field lines are coming out of the table.
15.  Ans: (a) The maximum force is exerted on a current carrying conductor only when it is perpendicular to the direction of magnetic field.
(b)The minimum force or can say no force acts on a current carrying conductor when it is parallel to the magnetic field.
   For Online Help Log to www.jsuniltutorial.weeebly.com
Labels:

Comments

Post a Comment

CBSE ADDA :By Jsunil Sir : Your Ultimate Destination for CBSE Exam Preparation and Academic Insights

Class 10 Chapter 02 Acid Bases and Salts NCERT Activity Explanation

By
NCERT Activity Chapter 02 Acid Bases and Salt Class 10 Chemistry Activity 2.1 Indicator Acid Base Red litmus No Change Blue Blue Litmus Red No change Phenolphthalein Colourless Pink Methyl Orange Pink   Yellow Indictors are substance which change colour in acidic or basic media. Activity 2.2 There are some substances whose odour changes in in acidic or basic media. These are called olfactory indicators. Like onion vanilla, onion and clove. These changes smell in basic solution. Activity 2.3 Take about 5 mL of dilute sulphuric acid in a test tube and add few pieces of zinc granules to it. => You will observe bubbles of hydrogen gas on the surface of zinc granules. Zn + H2SO4 --> ZnSO4 + H2 => Pass the Hydrogen gas through the soap solution. Bubbles formed in the soap solution as Hydrogen gas it does not get dissolved in it
Post a Comment
Read more

CBSE I NCERT 10th Numerical Problem solved Reflection and reflection of light

By
Q. 1. A concave mirror of focal length 20cm is placed 50 cm from a wall. How far from the wall an object be placed to form its real image on the wall?  Solution: V= -50 cm F= -20cm From mirror formula 1/u = 1/f – 1/v = -1/20+ 1/50 = - 3/100  U = - 33.3 cm Therefore, the distance of the object from the wall x =  50 – u X = 50 – 33.3 = 16.7 cm. Q.2. An object is placed at a distance of 40cm from a concave mirror of focal length 15cm. If the object is displaced through a distance of 20 cm towards the mirror, By how much distance is the image displaced? Answer: Here f = - 15 cm, u = - 40 cm Now 1/f = 1/u + 1/v Then 1/v = 1/f – 1/u Or V= uf/u-f =( - 40 x -15)/25 = -24 cm Then object is displaced towards the mirror let u1 be the distance object from the Mirror in its new position. Then u1 = -(40-20) = -20cm If the image is formed at a distance u1 from the mirror then v1 = u1f/u1-f = -20X-15/-20+15 = -60 cm. = - 20 x-15/-20+15 = -60 cm. Therefor
2 comments
Read more

Class 10 Metal and Non MetalsChapter 03 NCERT Activity Solutions

By
X Class 10 NCERT Activity Explanation Class 10 Metals and Non Metals Activity 3.1 Page No. 37 Take samples of iron, copper, aluminium and magnesium. Note the appearance of each sample. They have a shining surface. Clean the surface of each sample by rubbing them with sand paper and note their appearance again. They become more shiny. => Freshly cut Metal have shiny surface Activity 3.2 Page No. 37 Take small pieces of iron, copper, aluminium, and magnesium. Try to cut these metals with a sharp knife and note your observations. They are very hard to cut. Hold a piece of sodium metal with a pair of tongs and try to cut it with a knife. Sodium can be cut easily with knife. Hence K and Na are soft metal cut with knife Activity 3.3 Page No. 38 Take pieces of iron, zinc, lead and copper try to strike it four or five times with a hammer. These metals are beaten into thin sheet on hammering. This property of metal is called malleability and metals are called malleable. Activity 3.4 Page
Post a Comment
Read more

Living science ratna sagar class 6 solutions

By
Ratna sagar living science 6 answers by jsunil. Class6 Living science solution Term-1 Living Science Solution chapter-1 Source of food Download File Living Science Solution chapter-2 Component of food Download File Living Science Solution chapter-3 Fibre to fabric Download File Living Science Sol ch-4 Sorting of material into group Download File Living Science Soln ch-5 Separation of substance Download File Living Science Solution chapter-6 Change around Us Download File Living Science Solution ch-7 Living and Non Living Download File Living Science Solution ch-8 Getting to Know Plants Download File Living Science Sol ch-9 The Body and Its movements Download File Visit given link for full answer Class6 Living science solution Term-II
Post a Comment
Read more

Electricity numerical for class 10 CBSE Trend Setter 50 Problems

By
1. The current passing through a room heater has been halved. What will happen to the heat produced by it? 2. An electric iron of resistance 20 ohm draws a current of 5 amperes. Calculate the heat produced in 30 seconds. 3. An electric heater of resistance 8 ohm takes a current of 15 A from the mains supply line. Calculate the rate at which heat is developed in the heater. 4. A resistance of 40 ohms and one of 60 ohms are arranged in series across 220 volt supply. Find the heat in joules produced by this combination in half a minute. 5. A resistance of 25 ohm is connected to a 12 V battery. Calculate the heat energy in joules generated per minute. 6. 100 joules of heat is produced per second in a 4 ohm resistor. What is the potential difference across the resistor? 7. An electric iron is connected to the mains power supply of 220 V. When the electric iron is adjusted at minimum heating’ it consumes a power of 360 W but at ‘maximum heating’ it takes a power of 840 W. Ca
Post a Comment
Read more