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From a certain tower of unknown height, it is found that the maximum range of R at a certain projection velocity u is obtained for a projection angle of θ. Derive u in terms of R, g and θ.
Answer is given as u = √ [ R g tan θ ]
Please expalin.
Its answer is 68.76 degree centigrade.Can anybody explain this ?
If the vectors a, b, c are co-planar, prove that the following determinant is zero.
Determinant first row: a, b, c
Determinant second row: a.a, a.b, a.c
Determinant third row: b.a, b.b, b.c
Note: Due to typing difficulty, the determinant is shown as above. Further, the vecor notation above a, b, c are not shown due to typing difficulty.
Whether the following statement is true or false?
1-phenyl ethanol will give a positive iodoform test.
Answer is given as false. I feel the answer should be true. Please confirm. If answer is false, please explain.
An ideal pendulum was oscillating with an angular amplitude Θ = ∏/3 inside a stationary elevator. When the pendulum was passing through its equilibrium position, the lift suddenly starts moving upward with an acceleration a = g. Find the new angular amplitude of the oscillation.
a) ∏/3
b) ∏/6
c) cos-13/4
d) ∏/2
Answer is given as option c). Kindly explain.
Optically active 2-iodobutane on treatment with NaI in acetone gives a product which does not show optical activity.Why.
\( \int_{-\left( \Pi \right)}^{ \Pi } \frac{xsinx}{1+e^{x}} \,dx\)
is
a) 1/2
b) 3/2
c) 2
d) 1
Answer is given as d). Kindly explain.
Let y = l2 - l3/z where l = 2.0 \( \pm 0.1\) , z= 1.0\( \pm 0.1\) then the value of y is given by
a) 2 \( \pm 0.8\)
b) -4 \( \pm 1.6\)
c) -4 \( \pm 0.8\)
d) none of these.
Answer is given as b). Kindly explain.
If the error in the measurement of the momentum of a particle is +100% then the error in the measurement of the kinetic energy is
a) 400%
b) 300%
c) 100%
d) 200%
Answer is given as b). Kindly explain.
The rms value of the electric field of light coming from the Sun is 720 Newton per coloumb. The average total energy density of the electromagnetic wave is
a) 4.58 * 10-6 J m-3
b) 6.37 * 10-9 J m-3
c) 81.35 * 10-12 J m-3
d) 3.3 * 10-3 J m-3
Answer is given as a). Kindly give explanation.