The answer to the blank above is 20. The speed limit given provided that you cannot see the tracks for 400 ft in both directions is always 20 mph. Basically, this 20 mph is decided based upon the traffic laws in order to avoid road casualties. Since it is "uncontrolled railroad crossing", the minimum speed should be implemented to slow down for the purpose of traffic calming measures. Other than this, the 20 mph is also applicable in narrowing roads as well as speed humps.
Answer
Hi,
correct answer is {D} 3.5 m/s²
Explanation
Acceleration is the rate of change of velocity with time. Acceleration can occur when a moving body is speeding up, slowing down or changing direction.
Acceleration is calculated by the equation =change in velocity/change in time
a= {velocity final-velocity initial}/(change in time)
a=v-u/Δt
The units for acceleration is meters per second square m/s²
In this example, initial velocity =2.0m/s⇒u
Final velocity=44.0m/s⇒v
Time taken for change in velocity=12 s⇒Δt
a= (44-2)/12 = 42/12
3.5 m/s²
Best Wishes!
Answer:
178200
g mile pounds
Explanation:
Work= Force * Distance= Fh
F=ma=mg where m is mass and g is acceleration due to gravity
Work= 165 pounds *g* 1080 m= 178200
g mile pounds
I really wish I could be helping you. I don't know.
Answer with Explanation:
We are given that
Radius of solid core wire=r=2.28 mm=

Radius of each strand of thin wire=r'=0.456 mm=
Current density of each wire=
a.Area =
Where 
Using the formula
Cross section area of copper wire has solid core =
Current density =
Using the formula


Total number of strands=19
Area of strand wire=




b.Resistivity of copper wire=
Length of each wire =6.25 m
Resistance, R=
Using the formula
Resistance of solid core wire=
Resistance of strand wire=