Answer:
v = 14.35 m/s
Explanation:
As we know that crate is placed on rough bed
so here when pickup will take a turn around a circle then in that case the friction force on the crate will provide the necessary centripetal force on the crate
So here we have

here we have

now we know that

here we have

R = 35 m
g = 9.81 m/s/s
now plug in all values in above equation

As the air becomes warmer, heat<span> is transferred </span>between<span> molecules and kinetic</span>energy<span> is created which produces </span>thermal energy<span>. As the molecules move faster to transfer </span>heat<span>, the </span>temperature<span> also increases.</span>
Answer:
Speed of sound inside metal is ≅ 8200 
Explanation:
Given :
Length of metal bar
m
From general velocity equation,

Where
speed of sound in air = 343 
For finding time from above equation,


sec
Since pulses are separated by
sec
So we take time difference,

So speed of sound in metal is,



<u>Answers
</u>
1) B. longitudinal.
2) B. air is cooler than the ground.
<u>Explanation
</u>
Q1
There are two categories of a wave. That is transverse and longitudinal waves. Transverse waves forms crests and troughs while longitudinal forms compressions and rarefaction as they travel. Rarefactions are regions where the wavelengths are longer than other regions.
Q2
As the ray of light moves from an optically less dense to a more dense region it bends towards the normal.
If the sound is bending away from the earth's surface, then the ground must be warmer than the air. As the sound travels it moves from optically dense medium to a less dense medium. For this reason it bends away from the normal. This can only happen when, B. air is cooler than the ground.
Answer:
v = 15 [m/s]
Explanation:
To solve this problem we must use the principle of conservation of linear momentum, which tells us that momentum is equal to the product of mass by Velocity.

where:
P = linear momentum [kg*m/s]
m = mass = 2 [kg]
v = velocity = 15 [m/s]
![P=2*15\\P=30 [kg*m/s]](https://tex.z-dn.net/?f=P%3D2%2A15%5C%5CP%3D30%20%5Bkg%2Am%2Fs%5D)
Since we know that momentum is conserved, that is, all momentum is transferred to the second body, we can determine the velocity of the second body, since the mass is equal to that of the first body.
![30=2*v\\v = 30/2\\v = 15 [m/s]](https://tex.z-dn.net/?f=30%3D2%2Av%5C%5Cv%20%3D%2030%2F2%5C%5Cv%20%3D%2015%20%5Bm%2Fs%5D)