Class 11th

Block of mass M slides down on frictionless incline as shown. The minimum friction coefficient so that block of mass m does not slide with respect to lower block is close to $\frac{I}{1000}$ , the nearest integer to I is $?\left(\mathrm{s}\mathrm{i}\mathrm{n}?{37}^{?}\approx \frac{3}{5}\right)\left\{\right.$ Take $\left.g=10\mathrm{m}/{\mathrm{s}}^2\right\}$

Incorrectly matched among the following is:

The torque $\stackrel{?}{\tau }$ acts on a body about a given point is found to be equal to $\stackrel{?}{A}*\stackrel{?}{L}$ where $\stackrel{?}{A}$ is a constant nonzero vector and $\stackrel{?}{L}$ is the angular momentum of the body about that point. Choose the incorrect option: $(\stackrel{?}{A}\ne \pm \hat{L})$

Out of the following, which is the correct match for radial probability of finding the electron of 2s orbital?

Which of the following ionic species has maximum ionization energy?

A particle of mass 3 kg moving with speed of 3 m/s is acted upon by an impulse. As a result, the particle starts moving in a direction 90° to the original direction with a speed of 4 m/s. Find the impulse acted upon on the particle in SI units.

Speed of sound in a resonance tube experiment is given by the expression v = 2f₀(l₂ – l₁) where f? is the frequency of the tuning fork and l₁, l₂ are length of the air column. Consider f₀ = 300 Hz with no error in its value. Lengths of the air column l₁ and l₂ are measured as 25.0 cm and 80.0 cm respectively. Find the absolute error in the speed of sound (in m/s).

A wooden wheel having radius of 1 m is to be fitted with an iron ring around it. The diameter of the ring is 6 mm smaller than the wooden wheel. If the coefficient of linear expansion of iron is 1.2 * 10^-5/ °C, then find the minimum increase in temperature (in °C) to fit the ring on the wheel.

A bucket of height 20 cm is placed under a tap such that water flows into the bucket at a constant rate of 100 cm³/s. There is a small hole in the bucket of cross-sectional area of 1 cm² at height of 3 cm from the bottom. Area of hole is very small as compared to area of the bucket. Find the maximum height (in cm ) above the bottom upto which the water is filled in the bucket. (Take g = 10 m/s² )