-
$\text{3V}\cos\theta$
-
$2\text{V}\cos\theta$
-
$\frac{3}{2}\text{V}\cos\theta$
-
$\text{V}\cos\theta$
$\text{3V}\cos\theta$
$2\text{V}\cos\theta$
$\frac{3}{2}\text{V}\cos\theta$
$\text{V}\cos\theta$
Explanation:
The linear momentum is conserved in horizontal direction.

Initial momentum = Final momentum
$\Rightarrow\text{mv}\cos\theta=-\frac{\text{m}}{2}\text{v}\cos\theta+\frac{\text{m}}{2}\text{v}'$
$\Rightarrow\text{v}'=\text{mv}\cos\theta$
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(a) Stationary |
(b) Moving towards earth |
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(c) Moving away from earth |
(d) Information is incomplete |
The angle of dip at a place is 40.6o and the intensity of the vertical component of the earth's magnetic field V = 6 Tesla. The total intensity of the earth's magnetic field (I) at this place is
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(a) 7 |
(b) 6 |
(c) 5 |
(d) 9.2 |
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(b) Disimilarity of radii of curvature |
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(c) Variation of focal length of lenses with wavelength |
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(d) None of these |
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and
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(a) 4F |
(b) 2F |
(c) |
(d) |
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(a) The N-end is connected to the positive terminal of the battery |
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(b) The P-end is connected to the positive terminal of the battery |
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(c) The direction of current is from N-end to P-end in the diode |
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(d) The P-end is connected to the negative terminal of battery |
A slit of size 0.15 cm is placed at 2.1 m from a screen. On illuminated it by a light of wavelength 5 × 10–5 cm. The width of central maxima will be
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(a) 70 mm |
(b) 0.14 mm |
(c) 1.4 mm |
(d) 0.14 cm |