**Explanation:**

u=0, v=?, a=5m/s², t=8sec

So, by the formula,

v=u+at

v=0+5×8

v=40m/s.

hope this helps you .

**Sound **

is a compression wave of gas, liquid, or solid, that is detected by your ear.

**Answer:**

0.629 m

**Explanation:**

For destructive interference we have the case

m = 1,2,3.....

Frequency is given by

Wavelength

The angle

The width is

**The width of the hole is 0.629 m**

For destructive interference

The angles are

**Answer:**

Their common velocity after collision is **3.6 m/s**

**Explanation:**

Given;

mass of the first meatball, m₁ = 3.0 kg

initial velocity of the first meatball, u₁ = 6.0 m/s

mass of the second meatball, m₂ = 2.0 kg

initial velocity of the first meatball, u₂ = 0 m/s

let their common velocity after collision = v

Apply the principle of conservation of linear momentum for inelastic collision ;

m₁u₁ + m₂u₂ = v(m₁ + m₂)

(3 x 6) + (2 x 0) = v( 3 + 2)

18 = 5v

v = 18 / 5

**v = 3.6 m/s**

Therefore, their common velocity after collision is **3.6 m/s**