Answer:
The net force acting on an object is proportional to the acceleration of that object with respect to an inertial frame of reference. The constant of proportionality in this, Newton's second law, is the classical mass of the object.
Explanation:
Answer:
B) the law of reflection
Explanation:
When a light ray reflects off a surface, it obeys the law of reflection.
A few definitions before giving the law of reflection:
- The angle of incidence is defined as the angle between the incident ray and the normal to the surface
- The angle of reflection is defined as the angle between the reflected ray and the normal to the surface
The law of reflection states that:
- The angle of incidence is equal to the angle of reflection
- The incident ray and the reflected ray lie both on the same plane.
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

Acceleration = (force) / (mass)
If there is no friction . . .
Acceleration = (200N) / (50 kg) = 4m/s²
Change in speed = (acceleration) x (time) = (4 m/s²) x (10 sec) = 40 m/s
<em>Final speed = (speed of the cart before the force began) + (40 m/s more)</em>
(That's about <em><u>89 mph faster</u></em> than the cart was moving before the force started.)