#jeemain
- An open beaker of water in quilibrium with water vapour is in a sealed container. When a few grams of glucose Answer: (1) the rate at which water molecules leave the solution decreases At equilibrium, the rate of evaporation (water molecules leaving... 1
- Four small balls are placed at the corner of a square of length l. Evaluate MOI of system about a line passing through A and parallel to BD. The correct option is 2) 3 ml² I=2m(loversqrt2)² +m(sqrt2l)² =2ml²over 2+2ml²=3ml² 1
- In photoelectric effect stopping potential for electromagnetic radiations depends on Correct option is 4)frequency In photoelectric effect stopping potential for electromagnetic radiations depends on frequency 1
- Consider two satellites S1 and S2 with periods of revolution 1 hr and 8 hr respectively revolving around a planet in circular orbits. The correct answer is A) 8:1 we have formula, ω = 2over T given the, ratio of time period T₁over T₂=1over8 from formula, ω ∝ 1over T ω₁ over... 1
- A block of mass m, lying on a smooth horizontal surface, is attached to a spring (of negligible mass) of spring constant k. the correct answer is option C) Fover√(mk) Detailed solution:: Maximum speed is at mean position (equilibrium). F = kx x=Fover k W_F + W_sp... 1
- The line x + y = 2 is tangent to the curve x2 = 3 - 2y at its point x²= 3 – 2y 2x = 0 – 2 (dy / dx) ⇒ dy / dx = – x The slope of the tangent of the curve is -x. From the given information of the line, the slo... 1
- If sec 4θ − sec 2θ = 2, then find the general value of θ Answer is θ=nπ+π/2 or nπ/5+π/2 Explanation:: Video Solution:: https://youtu.be/pWg7L988Dt8 1
- The greatest coefficient in the expansion of (1+x) 2n+2 is correct option is B) (2n+2)!over [(n+1)!]² 1
- If z is a complex number, then the minimum value of |z| + |z − 1| is ______. First, note that |-z|=|z| and |z1 + z2| ≤ |z1| + |z2| Now |z| + |z-1| = |z| + |1 - z| ≤ |z + (1 - z)| = |1| = 1 Hence, minimum value of |z|... 2
- If (1 + i) (1 + 2i) (1 + 3i) ….. (1 + ni) = x + iy, then what is 2 * 5 * 10….(1 + n2) is equal to? option C) is the correct detailed solution :: We have (1 + i) (1 + 2i) (1 + 3i) ….. (1 + ni) = x + iy …..(i) (1 − i) (1 − 2i) (1 − 3i) ….. (... 1
- For three events A, B and C, P(Exactly one of A or B occurs) = P(Exactly one of B or C occurs) = P(Exactly one of C or A occurs) = 1/4 The correct answer is option B)7/16 P(A) + P(B) – 2P (A ∩ B) = 1/4 P(B) + P(C) – 2P(B ∩C) = 1/4 P(A) + P(C) – 2P(A ∩ C) = 1/4 P (A ∩ B ∩ C)... 1
- If 12 identical balls are to be placed in 3 identical boxes, then the probability that one of the boxes contains exactly 3 balls, is The correct answer is A)55/3(2/3)¹1 Explanation:: There are 12 balls and they are identical. And 3 identical boxes. That hspace0.2cmmeans hs... 1
- The number of solution of the equation x+2tanx=π/2 in interval [0,2π] is The correct answer is 3 interval For more information and video solution visit Link not available 1
- The correct pair of the ambident nucleophiles is are: The correct answer is 3) A and C only Explaination : Ambident nucleophile means in a nucleophile more than one electron donor atom. Eg in NO... 2
- Let A={θϵ(-π/2π):3+2isinθ/1-2isinθ is purely imaginary} then the sum of elements in A is The correct answer is D)2π/3 Detailed answer 1
- The sum of all values of θ ∈ (0, π/2) satisfying sin2 2θ + cos4 2θ = 3/4 is Your answer is here 2
- If 5(tan 2 x−cos 2 x)=2cos2x+9, then the value of cos4x is See the below image , 2
- The kinetic energy needed to project a body of mass m from the earth surface (radius R) to infinity is V_(e= √(2gR) _______ Formula of Escape velocity) _( ).^(.). Kinetic Energy = 1over2mv_e²= 1over2m×2gR mgR option C is correct 1
- In a transistor if increase in emitter current is 4 mA and corresponding increase in collector triangle I_E=4 \\ \\ \\ triangle I_c=3.5 \ \\α=triangle I_c over triangle I_E = 3.5over4=7over8 \\ \\ β= αover1-α=7over8over 1- 7over8=7 Hen... 1
- If two identical capacitor once connected in series (Ceq = C1) and once connected in parallel So Your answer is D c₁over c₂=1over4 1
- A pulley of radius 2 m is rotated about its axis by a force F =20t-5t2 newton Torque is given by τ = FR Or α = FR/I Given F =20t – 5t2 R = 2m, I = 10 kgm2 α = (20t-5t²)×2over 10 α = 4t – t 2 ω=∫_t²α dt=2t²-t³/3 at ω =0... 1
- A particle undergoes uniform circular motion. About which point on the plane of the circle, The force will pass through the centre of the circle. Therefore, the angular momentum will remain conserved at the centre of the circle. hen... 1
- Two-point masses of 0.3kg and 0.7kg are fixed at the ends of a rod which is of length Work-energy theorem, W_allforces= 1over2 Iw² Given: w is constant So required work done to be minimum implies that I must be minimum. Let th... 1