Formula for final velocity: Vf= vi+(a*t)
Vi- initial velocity, a=acceleration, t-time
Vf=vi+(at)
Vf= 0+(9.8m/s*2.8s)
Vf= 27.44 m/s
The acceleration of the Earth when dropping something would be 9.8 m/s
Here is an reference that can help you answer problems like these.
Hope this helps and good luck :)
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.
What kind of analogy is this?
A. synonyms
B. part to whole
C. degrees of intensity
<span>D. cause to effect
This is because a synonym refers to things like "normal" or "regular" like your calling someone something.
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A "screen" or even just a set of parallel bars are highly reflective to electromagnetic waves as long as the open spaces are small compared to the wavelengths.
"Grid" dishes work fine ... with less weight and less wind resistance ... for frequencies below about 3 GHz. (Wavelengths of at least 10 cm.)
(I even worked on a microwave system in South America where huge grid dishes were used on a 90-mile link.)
Answer:
ΔT = 302 °c
Explanation:
mass (m) = 4.6 g = 0.0046 kg
velocity (v) = 278 m/s
specific heat of lead (c) = 128 J/kg. °c
kinetic energy = 0.5 mx 
kinetic energy = 0.5 x 0.0046 x 
kinetic energy = 177.8 J
since all the kinetic energy is converted to thermal energy,
kinetic energy = thermal energy (E) = 177.8 J
thermal energy = m x c x ΔT
where ΔT is the temperature change
177.8 = 0.0046 x 128 x ΔT
ΔT = 177.8 / 0.59
ΔT = 302 °c
