Answer:
3.9 seconds
Explanation:
Use constant acceleration equation:
y = y₀ + v₀ t + ½ at²
where y is the final position,
y₀ is the initial position,
v₀ is the initial velocity,
a is the acceleration,
and t is time.
Given:
y = 0 m
y₀ = 15 m
v₀ = 15 m/s
a = -9.8 m/s²
Substituting values:
0 = 15 + 15t + ½ (-9.8) t²
0 = 15 + 15t − 4.9t²
0 = 4.9t² − 15t − 15
Solve with quadratic formula:
t = [ -b ± √(b² − 4ac) ] / 2a
t = [ 15 ± √((-15)² − 4(4.9)(-15)) ] / 2(4.9)
t = [ 15 ± √(225 + 294) ] / 9.8
t = (15 ± √519) / 9.8
t = -0.79 or 3.9
It takes 3.9 seconds for the stone to reach the bottom of the well.
The negative answer is the time it takes the stone to travel from the bottom of the well up to the top of the well.
Answer:
a) 4.9 s
b) 167.8 m
Explanation:
Hello!
To solve this question we need to make use of the equations of motion of both the motorcycle xm(t) and the car xc(t) at t=5
Let us consider the position of the motorcycle at t=5 as the origin, that is:
xm(t+5) = vt + (1/2)at^2
xc(t+5) = vt + 60 m
where v = 22.0m/s and a=5m/s^2
We are looking for the time t' when the position of the car and the motorcycle are the same:
xm(t'+5)=xc(t'+5)
vt' + (1/2)at'^2 = vt' +60m
t' = √(120 m /a) = 4.89898... s
Since we are considering the origin of the cooordinate system at the position when the motorcycle starts to accelerate, the distance travelled by the motorcycle until it catches the car is given by:
xm(t'+5)= vt' + (1/2)at'^2
xm(9.89898s) = (22 * 9.89898 + 2.5 * 9.89898^2)m
xm(9.89898s)= 167.777... m
Incompletevquestion. However, I inferred from a general perspective about perpendicular lines.
<u>Explanation:</u>
Put simply, <u>perpendicular lines</u> are lines that are at right angles (90°) to each other. Thus, we could say based on this definition that for lines lll and mmm to be perpendicular they intersect and be at right angles (90°) to each other as <u>found on the attached image.</u>
She observes solubility - the ability of the substance to dissolve in e.g. the liquid.
<span>Water in the oceans may become fresh water available to humans through the processes of evaporation, condensation and precipitation.
In these processes, water is heated to a very high temperature until it evaporates in order to kill the germs and remove the salts which remains after water evaporation. The next step in condensing the water vapor (which is now fresh) and precipitating this vapor to be used by humans.</span>
