Answer:
(a). The work done is 472 J.
(b). The force exerted is 2.76 kN.
Explanation:
Given that,
Distance = 17.1 cm
Mass of object = 281.5 kg
(a). We need to calculate the work done
Using formula of work done


Where, m = mass
g = acceleration due to gravity
d = distance
Put the value into the formula


The work done is 472 J.
(b). We need to calculate the force
Using action reaction principle


Put the value into the formula


The force exerted is 2.76 kN.
Hence, (a). The work done is 472 J.
(b). The force exerted is 2.76 kN.
Answer:
The time taken for the race is 17.20 s.
Explanation:
It is given in the problem that a 62.0 kg sprinter starts a race with an acceleration of 1.44 meter per second square.The initial speed of the sprinter is zero as it starts from the rest.
Calculate the final speed of the sprinter.
The expression for the equation of the motion is as follows;

Here, u is the initial speed, v is the final speed, a is the acceleration and s is the distance.
Put u= 0, s=30 m and
.


Calculate time taken to cover 30 m distance.
The expression for the equation of motion is as follows;

Put u= 0, s=30 m and
.

t=6.45 s
Calculate the time taken to complete his race.
T= t+t'
Here, t is the time taken to cover 30 m distance and t' is the time taken to cover 100 m distance.

Put s= 30 m,
and s'= 100 m.

T= 17.20 s
Therefore, the time taken for the race is 17.20 s.
The answer is variant C because every living organism needs water to survive. A human can live without water only 6 days, after that period the most important organs start to shut down because of the lack of water.
Answer:
A: The frequency of the vibration is 1.3329 Hz
B: The total energy of the vibration is 18.39375 J
Explanation:
The force of the man his weight causes the raft to sink, and that causes the water to put a larger upward force on the raft. This extra force is a restoring force, because it is in the opposite direction of the force put on the raft by the man. Then when the man steps off, the restoring force pushes upward on the raft, and thus the raft – water system acts like a spring, with a spring constant found as follows:
k= F/x = ((75 kg) * (9.81 m/s²))/(5*10^-2 m) = 14715 N/m
The frequency of the vibration is determined by the spring constant (k) and the mass of the raft (210kg).
fn = 1/2π * √(k/m) = 1/2π * √(14715 / 210) = <u>1.3329 Hz</u>
<u>The frequency of the vibration is 1.3329 Hz</u>
<u />
<u>b) </u>
Since the gravitational potential energy can be ignored, the total energy will be :
Etot = 1/2 k* A² = 1/2 * (14715 )*(0.05)² = 18.39375 J
<u>The total energy of the vibration is 18.39375 J</u>
god is mighty not only did he create the universe but also everything in it
but here's the answer 93 billion light years