Answer:
58.24 Km/h.
Explanation:
From the question given above, the following data were obtained:
Distance (d) = 495 Km
Time (t) = 8 h 30 mins
Speed (S) =?
Next, we shall express 8 hours 30 mins to hours.
We'll begin by convert 30 mins to hour.
60 mins = 1 h
Therefore,
30 mins = 30 mins × 1 h/ 60 mins
30 mins = 0.5 hour.
Thus,
8 h 30 min = 8 + 0.5 = 8.5 hours
Speed is define as the distance travelled per unit time. Mathematically, it is expressed as:
Speed = Distance /time
With the above formula, we can obtain the speed as shown below:
Distance (d) = 495 Km
Time (t) = 8.5 hour
Speed (S) =?
Speed = Distance /time
Speed = 495 Km / 8.5 hour
Speed = 58.24 Km/h
Thus, the speed is 58.24 Km/h.
Answer:
vf = 11.2 m/s
Explanation:
m = 10 Kg
F = 2*10² N
x = 4.00 m
μ = 0.44
vi = 0 m/s
vf = ?
We can apply Newton's 2nd Law
∑ Fx = m*a (→)
F - Ffriction = m*a ⇒ F - (μ*N) = F - (μ*m*g) = m*a ⇒ a = (F - μ*m*g)/m
⇒ a = (2*10² N - 0.44*10 Kg*9.81 m/s²)/10 Kg = 15.6836 m/s²
then , we use the equation
vf² = vi² + 2*a*x ⇒ vf = √(vi² + 2*a*x)
⇒ vf = √((0)² + 2*(15.6836 m/s²)*(4.00m)) = 11.2 m/s
The two points on a periodic wave in a medium are said to be in phase if they have the same amplitude and are moving in the same direction.
Option 4.
Explanation:
A periodic wave is termed for waves which flow in a repetition pattern in a given time scale. Periodic wave can also be termed as a transverse wave. So a transverse wave have various crests and troughs. The two successive crests and two successive troughs are said to be in phase with each other.
Thus, for a periodic wave in a medium, the in phase can be obtained in two points which have the same amplitude and are moving in the same direction.
As amplitude is a scalar quantity and so direction should be taken into consideration for making the points related to successive crests only in phase with themselves. Also this also relates the points related to successive troughs to be in phase with each other. But a crest and a trough will not be in phase with each other.
Thus, option 4, that is the two points on a periodic wave in a medium are said to be in phase if they have the same amplitude and are moving in the same direction.
The answer is D, it increases the susceptibility to infections.
