Moving Charges and Magnetism

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Explanation – here A and B vectors are joint by head and tail. So C= A+B

(a) from fig iv it is clear that c=a+b

(a) From fig iii it is clear that c+b=a so a-c=b

(b) From fig I it is clear that b=a+c so b-a =c

(c) From ii it is clea

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Explanation – a) radius of earth =6400km= 6.4 $\times {10}^{6}m$

Time period = 1 day = 24 $\times 60\times 60$ = 86400s

Centripetal acceleration a= w²r= R(2 $\pi /T$ )²=4 $\pi$ ²R/T

= $\frac{4\times {\left(\frac{22}{7}\right)}^2\times 6.4\times {10}^6}{({24\times 60\times 60)}^2}$ = 0.034m/s²

b) time = 1yr=365 $\times 24\times 60\times 60$ days= 365=3.15 $\times {10}^{7}s$

centripetal acceleration = Rw²= $\frac{4{\pi }^{2}R}{T^2}$

^{$=\frac{4\times {\frac{22}{7}}^2\times 1.5\times {10}^{11}}{({3.15\times {10}^7)}^2}=5.97\times {10}^{-3}m/s$ 2}

$\frac{a_c}{g}=\frac{5.97\times {10}^{-3}}{9.8}=\frac{1}{1642}$

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Explanation- when it be at position P, drops a bomb to hit a target T

Let $\theta$

Speed of the plane =720km/h = 720 $\times 5/18$ = 200m/s

Altitude of the plane P’T = 1.5km= 1500m

If bomb hits the target after time t then horizontal distance travelled b

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Explanation – due to air resistance particle energy as well as horizontal component of velocity keep on decreasing making the fall steeper then rise. When we are neglecting air resistance path is parabola when we consider air resis

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Explanation – The boy throws the ball at an angle of 60.

Horizontal component of velocity 4cos $?$ = 10cos60

=10 (1/2)

=5m/s.

so horizontal speed of the car is same, hence relative velocity of car and ball in the horizontal direction will

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Explanation – The path of the ball observed by a boy standing on the footpath is parabolic. The horizontal speed of the ball is same as that of the car, therefore ball as well car travels equal horizontal distance, due to vert

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Explanation – the direction of (B $*C$ ) will be perpendicular the plane containing B and B by right hand rule. A $*(B*C)$ will lie in the plane of B and C and is perpendicular to vector A.

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Explanation- if the football is kicked into the air vertically upwards. Acceleration of football will always vertically downwards and equal to acceleration due to gravity. But when it reaches the highest point its velocity is zero

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Explanation- at point B it will gain the same speed u and after that speed increases and will be maximum just before reaching point c.

During journey from O to A speed decreases and will be maximum at point A and acceleration is alw

This is a Short Answer Type Questions as classified in NCERT Exemplar

Explanation- vsin $\theta$ = vertical component

V_x= horizontal component of velocity =vcos $\theta$ = constant

V_y = vertical component of velocity =vsin $\theta$

Velocity will always be tangential to the curve in the direction of motion and acceleration is