<em>Answer: </em>
1. The <em>"contour interval'</em> identifies the standard difference in elevation on a topography graph. It shows the difference in elevation of highest and lowest points on a topography map. In topographic map every fifth contour line is drawn, wider than the contour lines, called as contour index.
2. Geologist usually study all the materials that make up the earth. He can focus on different rock samples from earth's surface. the geologist works to understand history of the planet where we live on, to predict the future by explaining current occurrences.
3. The difference between the top of the plateau and the lowest point in the area of 250 m measurement is called <em>elevation. </em><em>Elevation is the highest point in the area.</em>
<em>4. </em>Damage from earthquakes is determined by <em>"Ritcher scale"</em>. Seismic waves are the vibrations occurs from earthquakes that can travel through the earth. These vibrations can be detected by the Ritcher scale.
Explanation:
Fnet = ma.
Assume that there is no resistance acting on the mass. Therefore a = 15N / 45kg = 0.33N/kg or 0.33m/s^2.
When light passes from a faster medium into a slower medium, light will be refracted toward a line drawn perpendicular to the point of refraction. <em>(B)</em>
Answer:
Magnitude of the net force on q₁-
Fn₁=1403 N
Magnitude of the net force on q₂+
Fn₂= 810 N
Magnitude of the net force on q₃+
Fn₃= 810 N
Explanation:
Look at the attached graphic:
The charges of the same sign exert forces of repulsion and the charges of opposite sign exert forces of attraction.
Each of the charges experiences 2 forces and these forces are equal and we calculate them with Coulomb's law:
F= (k*q*q)/(d)²
F= (9*10⁹*3*10⁻⁶*3*10⁻⁶)(0.01)² =810N
Magnitude of the net force on q₁-
Fn₁x= 0
Fn₁y= 2*F*sin60 = 2*810*sin60° = 1403 N
Fn₁=1403 N
Magnitude of the net force on q₃+
Fn₃x= 810- 810 cos 60° = 405 N
Fn₃y= 810*sin 60° = 701.5 N
Fn₃ = 810 N
Magnitude of the net force on q₂+
Fn₂ = Fn₃ = 810 N
