The best answer would be the 4th choice. "They help scientists explain concepts that are difficult to observe, this also covers the first answer which helps the scientist to answer complex questions. A scientific model is not used prove scientific laws as they may not always have all the data to prove so, instead it is used to allow them to explain better concepts revolving around science through research and may also allow them to predict results based on the accumulation of data and analyzing the trend of this resulting information.
It's very hard to see the self-portrait, so I can't identify him.
Answer:
Intensity, 
Explanation:
Power of the light bulb, P = 40 W
Distance from screen, r = 1.7 m
Let I is the intensity of light incident on the screen. The power acting per unit area is called the intensity of the light. Its formula is given by :
So, the intensity of light is 
.
Answer:
x=2d
Explanation:
initial stretch in the spring is d
so using Hook's law
at equilibrium position
k×d=mg
where k= spring constant
m= mass of fish
g= acceleration due to gravity.
d=mg/k ................ (1)
in second case by energy conservation
1/2 kx^2=mgx
x=2mg/k
using equation 1
x=2d
Answer:
134r kgm^-1 or 1344 kg /m
Explanation:
Momentum is is given by:
p=mv
Where:
p is momentum, m is mass in kg and v is velocity in ms−1
p=120kg×11.2 m/ s= 1344 kgms=1344kgm^−1
