Answer:
The car will travel 30 miles during the 30-minutes period of acceleration.
Explanation:
Given data :
Initial velocity = v₁ = 50 miles/hour
Final velocity = v₂ = 70 miles/hour
Time = t = 30 min = 0.5 hour
Using the definition of acceleration, we find the acceleration (a)
a = (v₂ - v₁) ÷ t
a = (70 - 50) ÷ 0.5
a = 20 ÷ 0.5
a = 40 miles/hour²
Using 3rd equation of motion, we find the distance travel (s)
2as = v₂² - v₁²
2(40)s = 70² - 50²
80 × s = 4900 - 2500
s = 2400 ÷ 80
s = 30 miles
Answer:
When two forces acting on an object are equal in size but act in opposite directions, we say that they are balanced forces.
Explanation:
I do believe all of these but core elements can be determined by spectroscopy which includes the use of electromagnetic radiation. Both the surface and core temperature can be measured using light. Surface elements can be found because the absorption lines of different elements in the spectra of the star, but I haven't heard anything about using spectral analysis for core elements.