Answer :
Answer:
a. 42.92 m/s b 4.4 s c. 915.2 m
Explanation:
Here is the complete question
A volcano erupts, and a chunk of hot magma is launched horizontally with a speed of 208 m/s, from a height of 94 m. We can ignore air resistance.
What is the vertical velocity of the magma when it hits the ground?
Solution
a. Using v² = u² - 2gy since it is motion under gravity, where u = initial vertical velocity = 0 m/s, g = acceleration due to gravity = -9.8 m/s² and y = height = 94 m.
Substituting these values into the equation, we have
v² = u² - 2gy
v² = 0² - 2 × (-9.8 m/s²) × 94 m
v² = 1842.4 m²/s²
v = √1842.4 m²/s²
v = 42.92 m/s
b. We also find the time it takes to drop from the height of 94 m from
y = ut - 1/2gt² , u = 0
So, t = √(2y/g)
= √(2 × 94 m ÷ 9.8 m/s²)
= √19.184 s²
= 4.4 s
c. The horizontal distance the chunk of hot magma covers is thus x = Vt where v = horizontal velocity = 208 m/s
x = 208 m/s × 4.4 s = 915.2 m