Answer:
The child will take 5.952 seconds to travel from the top of the hill to the bottom.
Explanation:
Given that the child accelerates uniformly and that both initial (
) and final speeds (
), measured in meters per second, and acceleration (
), measured in meters per square second, are known, we proceed to use the following kinematic equation to determine the time taken to travel from the top of the hill to the bottom (
), measured in seconds, is:
(1)
If we know that 
, 
and 
, then the time taken is:
The child will take 5.952 seconds to travel from the top of the hill to the bottom.
... The top branch of the 3-branched parallel block ... the 9 and 6 in series ...
is equivalent to a single resistor of 15 ohms.
... The 3-branched parallel block boils down to (30, 10, and 15) in parallel.
That's (1/30 + 1/10 + 1/15)⁻¹ = 5 ohms.
... The 5-ohm-equivalent block and the 20-ohm resistor form a
voltage divider across the battery.
The voltage across the 5-ohm-equivalent block is (5/25 x 30v) = 6v .
... The top branch of the block is equivalent to a (9 + 6) = 15-ohmer.
With 6v across its ends, the current through that branch is (6/15) = 0.4A .
... With 0.4A flowing through it, the 9-ohm resistor is dissipating
I²R = (0.4A)² (9 ohms) = (0.16 A²) (9 ohms) = 1.44 W (choice-3)
Answer:
The speed of sound, in m/s, through air at this temperature is 343.5 m/s
Explanation:
Given;
distance traveled by sound, d = 1,687.5 meters
time taken for the sound to travel, t = 5 seconds
air temperature, θ = 10°C
Speed of sound = distance traveled by sound / time taken for the sound to travel
Speed of sound = d / t
= 1687.5 m / 5 s
= 337.5 m/s
Speed of sound at the given temperature is calculated as;
c = 337.5 + 0.6θ
c = 337.5 + 0.6 x 10
c = 337.5 + 6
c = 343.5 m/s
Therefore, the speed of sound, in m/s, through air at this temperature is 343.5 m/s
Answer:
A
Explanation:
ignore this on...............................
