Answer:
height = 45 m
Explanation:
Initial velocity = 0 m/s
Final velocity = 30 m/s
Acceleration due to gravity = +10m/s^2 ( because ball is going down )
Using the eqn of motion

where v= final velocity ; u = initial velocity ; g = acceleration due to gravity ; h = height
So,



Answer: <u>D. An AC circuit</u>
Explanation:
I took it on a test and it was correct ; )
Answer:
d.
50 m
Explanation:
v² = u² + 2as
s = (v² - u²) / 2a
s =(25² - 0²) / (2(6.25))
s = 50 m
Answer:
C) three
Explanation:
Let gram of gold required be m . Let temperature change in both be Δ t .
heat absorbed = mass x specific heat x change in temperature
for copper
heat absorbed = 1 x .385 x Δt
for gold
heat absorbed = m x .129 x Δt
So
m x .129 x Δt = 1 x .385 x Δt
m = 2.98
= 3 g approximately .