Since the question above is looking for the SPEEd of the WAVE, the formula that should be used is SPEED = DISTANCE / TIME. You just need to substitute the distance (36 meters) and the time (15 seconds) to the formula. You should be able to get SPEED = 2.4 m/s.
Answer:
The time the train blocked the crossway is
0.007934h=0.476 min=28.6 s
Explanation:
The average speed is given by
V= (Vi+Vf)/2
and
V= dx/dt
Where
Vi= initial speed
Vf= final speed
dx= change of position=0.384 km
dt=time the train blocked the crossway
dt=2dx/(Vi+Vf)
dt=2*0.384 km/(77.3 +19.5) km/h
dt=0.007934h
dt=0.007934h*(60min/1h)=0.476 min
dt=0.476 min*(60s/1min)=28.6 s
Answer:
when an object has more velocity, it tends to have less potential energy and more kinetic energy.
Explanation:
kinetic energy is the energy of movment and velocity helps to describe movement
Answer: YES
They always move towards the earth or any metallic conductor
Explanation:
Electric discharge between two objects follows a predictable path? YES
Static electricity is a buildup of electric charges on objects. Charges build up when negative electrons are transferred from one object to another. The object that gives up electrons becomes positively charged, and the object that accepts the electrons becomes negatively charged.
Once an object becomes electrically charged, it is likely to remain charged until it touches another object or at least comes very close to another object. That’s because electric charges cannot travel easily through air, especially if the air is dry.
They always move towards the earth or any metallic conductor
Answer:
13.5 ms
Explanation:
The sound wave travels with uniform motion in both cases, so the time taken to cover a distance d is given by:

where
d is the distance to cover
v = 340 m/s is the speed of sound in air
So for the people across the newsroom,
d = 4.7 m
So the time taken is

The radio waves instead travels with uniform motion at the speed of light:

So the time taken for them is

where
d = 82 km = 82,000 m
is the distance of the people who are 82 km away. Substituting,

Therefore, the difference in time is
