A hill is 500m high supplies are to be sent across the hill using a Cannon that can help as at a speed of 125ms^-1 over the hill.The Canon is located at the distance of 800m from the foot of the hill and can be moved on the ground at a speed of 2ms^-1 so that its distance from the hill can be adjusted.What is the shortest time in which a package can reach on the ground across the health (take G = 10 metre S -2)
Answers
E X P L A N A T I O N !
➨ Given:-
• Speed of the packets = 125 ms^-1
• Height of the hill = 500m
➨ To Find:-
Total time taken by the packet to reach on the ground = ?
➨Solution:-
⁍ To cross the hill, the vertical component of rhe velocity should be sufficient to cross such height.
uy ≥ √2gh
uy ≥ √2 × 10 × 500 ≥ 100 ms^-1
But,
u^2 = ux^2 + uy^2
⁍ Horizontal component of initial velocity,
ux = √ u^2 - uy^2 = √ (125)^2 - (100)^2
ux = 75 ms^-1
Time taken to reach the top of the hill,
t = √2h/g = √2×500/10 = 10s
Time taken to reach the Ground from the top of the hill,
• t' = t = 10s
∴ Horizontal distance travelled and 10s,
x = ux × t
x = 75 × 10
x = 750 m
⁍ Distance through which Canon has to be moved = 800- 750 = 50 m
Speed with which canon has can move
= 2 ms^-1
• Time taken by Canon = 50 /2
⇨t' = 25s
• Total taken by a packet to reach
on the ground = t' + t + t'
= 25 + 10 + 10 = 45s
∴ The shortest time in which a package can reach on the ground across the health is 45s !
━━━━━━━━━━━━━━━━━━━━━━━━━━
Explanation:
Plate tectonics is a scientific theory describing the large-scale motion of the plates making up Earth's lithosphere since tectonic processes began on Earth between 3.3 and 3.5 billion years ago. The model builds on the concept of continental drift, an idea developed during the first decades of the 20th century.