Answer:
22m/s
Explanation:
To find the velocity we employ the equation of free fall: v²=u²+2gh
where u is initial velocity, g is acceleration due to gravity h is the height, v is the velocity the moment it hits the ground, taking the direction towards gravity as positive.
Substituting for the values in the question we get:
v²=2×9.8m/s²×25m
v²=490m²/s²
v=22.14m/s which can be approximated to 22m/s
Answer:
(a) Melting point is 136.8°C
(b) Melting point is 278.24°F
Boiling point is 832.28°F
(c) Melting point is 409.8K
Boiling point is 717.6K
Explanation:
(a) 586.1°F = 5/9(586.1 - 32)°C = 307.8°C
Melting point = 444.6°C - 307.8°C = 136.8°C
(b) Melting point = 136.8°C = (9/5×136.8) + 32 = 278.24°F
Boiling point = 444.6°C = (9/5×444.6) + 32 = 832.28°F
(c) Melting point = 136.8°C = 136.8 + 273 = 409.8K
Boiling point = 444.6°C = 444.6 + 273 = 717.6K
Answer:

Explanation:
= Distance of Andromeda Galaxy from Earth = 
= Time taken = 
= Speed of light = 
We have the relation


The required answer is
.
Answer:
3. Is 180◦ out of phase with the original wave at the end.
Explanation:
Here when wave is reflected by the rigid boundary then due to the rigidly bounded particles at the end or boundary they have tendency not to move and remains fixed at their position.
Due to this fixed position we can say when wave reach at that end the particles will not move and they apply equal and opposite force at the particles of string
Due to this the reflected wave is transferred back into the string in opposite phase with respect to the initial wave
so here correct answer will be
3. Is 180◦ out of phase with the original wave at the end.