Standing waves Quiz 1

Question 1

A metal thread is stretched to a tension of $$314N$$. Its radius is $$ 1\,\,	ext{m}$$ and a density of $$	ext{100}\,\,	ext{kg/}{{	ext{m}}^{	ext{3}}}$$. Find the frequency of the wave if its wavelength is $$4	ext{m}$$?

Accepted Answer

$$0.25\,\,	ext{Hz}$$

Answer

$$10	ext{Hz}$$

Answer

$$1	ext{Hz}$$

Answer

$$	ext{2}	ext{.5 Hz}$$

Question 2

If velocity is changed by $$10\%$$ by changing tension in the rod. Then find $$\%$$ change in tension of rod?

Accepted Answer

$$20\%$$

Answer

$$10\%$$

Answer

$$30\%$$

Answer

$$40\%$$

Question 3

The wave equation is $$y=100\sin \left( 10\pi t-2\pi x \right)\,\,metre$$,where $$'x'$$ is in metres.Then the velocity of the wave is

Accepted Answer

$$5	ext{m/s}$$

Answer

$$10	ext{m/s}$$

Answer

$$1	ext{m/s}$$

Answer

$$	ext{Zero}$$

Question 4

If the wavelength of waves is $$\lambda =0.1\,m$$. Consider two points on a wave with $$\Delta \phi =\dfrac{2\pi }{5}$$. What is the distance between two points on this wave?

Accepted Answer

$$0.02	ext{m}$$

Answer

$$0.01	ext{m}$$

Answer

$$0.03	ext{m}$$

Answer

$$0.04	ext{m}$$

Question 5

Two waves describes as $${{y}_{1}}=10\cos \left( 0.1\pi +2\pi x \right)$$ and $${{y}_{2}}=5\cos \left( 0.2\pi +4\pi x \right)$$. What would be the ratio of their intensities?

Accepted Answer

$$1:1$$

Answer

$$2:3$$

Answer

$$2:1$$

Answer

$$1:2$$