Answer:
Explanation:
12 ÷ 5 = 2.4
2.4 x 6 = 14.4 = 15 days or 14 days and 4 hours
What is a hypothesis?
a tentative explanation for an observation
Definition of hypothesis in US English:
A supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.
A ) The displacement:
d = v o t - (gt²) / 2 =
= 19.6 m/s × 1 s - ( 9.8 m/s² x 1 s² ) / 2 =
= 19.6 m - 4.9 m = 14.7 m
b ) v = v o - g t
0 = 19.6 m/s - 9.8 t ( when the ball is at the highest point )
9.8 t = 19.6
t = 19.6 : 9.8
t = 2 s
h = v o t - (gt²)/2 = 19.6 x 2 - ( 9.8 x 4 ) / 2 = 39.2 - 19.6
h = 19.6 m
c ) h = gt² / 2
19.6 = 9.8 t²/2
9.8 t² = 39.2
t² = 39.2 : 9.8
t² = 4
t 2 = 2 s ( and we know that t 1 = 2 s )
t = t 1 + t 2 = 2 s + 2 s = 4 s
Efficacy is the ratio of light output from a lamp or a bulb to the electric power it consumes and is measured in lumens per watt (LPW).
In this case; the power is 4 watt and the number of lumens is 240.
Efficacy = lumens/power
= 240/4
= 60 lm/W
Thus the efficacy of the bulb is 60 lm/W