<span>Continental crust is less dense than oceanic crust </span>
Answer: observed frequency (f') = 511.97Hz
Explanation: when there is a relative motion between an observer and a sound source, the frequency of sound wave perceived by the observer is different from the frequency of originally sent out by the sound source.
This is called Doppler effect and given mathematically below as
f' = (v + v') /(v- vs) * f
f' = observed frequency
v = speed of sound in air = 340m/s
v' = velocity of observer= 45m/s
vs = velocity of source relative to observer = - 36m/s ( the negative sign came as a result of the fact that the velocity of the source is in opposite direction to the velocity of the observer)
f = original frequency of sound source = 500Hz
f' = (340 + 45)/{340 -(-36)} * 500
f' = 385/ (340 + 36) * 500
f' = 385/ 376 * 500
f' = 1.0239 * 500
f' = 511.97Hz
Answer: (d)
Explanation:
Given
Mass of the first ram 
The velocity of this ram is 
Mass of the second ram 
The velocity of this ram 
They combined after the collision
Conserving the momentum
![\Rightarrow m_1v_1+m_2v_2=(m_1+m_2)v\\\Rightarrow 49\times (-7)+52\times (9)=(52+49)v\\\Rightarrow v=\dfrac{125}{101}\ m/s \quad[\text{east}]](https://tex.z-dn.net/?f=%5CRightarrow%20m_1v_1%2Bm_2v_2%3D%28m_1%2Bm_2%29v%5C%5C%5CRightarrow%2049%5Ctimes%20%28-7%29%2B52%5Ctimes%20%289%29%3D%2852%2B49%29v%5C%5C%5CRightarrow%20v%3D%5Cdfrac%7B125%7D%7B101%7D%5C%20m%2Fs%20%5Cquad%5B%5Ctext%7Beast%7D%5D)
Momentum after the collision will be
Therefore, option (d) is correct
Answer: As with all metals, the alkali metals are malleable, ductile, and are good conductors of heat and electricity. The alkali metals are softer than most other metals.
Alkaline earth metals
The alkaline earth elements are metallic elements found in the second group of the periodic table
Explanation:
