Answer:
D. 48.985 N
Explanation:
Newton's second law states that:
which means that the net force acting on an object is equal to the product between the object's mass and its acceleration.
The equation of the forces for the briefcase in the elevator therefore is given by:
where
N is the normal reaction exerted on the briefcase
(mg) is the weight of the briefcase, with
m = 4.5 kg being its mass
g = 9.8 m/s^2 is the acceleration of gravity
a = 1.10 m/s^2 is the acceleration
Here we chose upward as positive direction.
Solving for N, we find the normal force:
So the closest answer is
D. 48.985 N
The work that Sam should do in order to stop is the boat is the same as that of the kinetic energy of the object in order to counter its motion. Kinetic energy is calculated through the equation,
KE = 0.5mv²
where KE is kinetic energy, m is mass, and v is the velocity.
Substituting,
KE = 0.5(1200kg)(1.2 m/s)²
<em>KE = 864 J</em>
Compression and rarefraction, the other guy's answer it's wrong
A. A solstice.
That is the correct answer.
Answer:
Zero
Explanation:
Acceleration is defined as the rate of change in speed. The speed during the first second is 9m/1s = 9m/s. During the second second is again 9m/1s = 9m/s and again 9m/s for the third second. Being the speed the same, the acceleration is 0
