The work done is the product between the intensity of the force applied F, the amount of the displacement d of the book and the cosine of the angle

between the direction of the force and the direction of the displacement:

In our problem, the student is lifting the book, so he is applying a force directed upward, and the book is moving upward, so F and d are parallel and therefore the angle is zero, so

Therefore, the work done is
Conociendo la longitud y frecuencia de un péndulo, queremos encontrar la longitud de otro pendulo de tal forma que tenga otra frecuencia.
Veremos que la longitud del nuevo péndulo debe ser 6.25m
Sabemos que un péndulo de 4m de longitud tiene una frecuencia de 5Hz.
La frecuencia de un péndulo está dada por:

Donde g es la aceleración gravitatoria y l es la longitud del péndulo, remplazando los datos que tenemos en esa ecuación obtenemos:

Ahora debemos encontra la longitud de tal forma que la frecuencia sea 4Hz, entonces debemos resolver:

La longitud del nuevo péndulo deve ser 6.25m
Sí quieres aprender más, puedes leer:
brainly.com/question/23483504
It is definitely an apple. I would know because i am a musician
Answer: The energy incident on the solar panel during that day is
.
Explanation:
Given: Mass = 250 kg
Initial temperature = 
Final temperature = 
Specific heat capacity = 4200 
Formula used to calculate the energy is as follows.

where,
q = heat energy
m = mass of substance
C = specific heat capacity
= initial temperature
= final temperature
Substitute the values into above formula as follows.

As it is given that water absorbs 25% of the energy incident on the solar panel. Hence, energy incident on the solar panel can be calculated as follows.

Thus, we can conclude that the energy incident on the solar panel during that day is
.
<span>Lateral epicondylitis, or “tennis elbow,” is an inflammation of the tendons that join the forearm muscles on the outside of the elbow. </span>The bony bump on the outside (lateral<span> side) of the </span>elbow<span> is called the </span>lateral epicondyle<span>. The ECRB muscle and tendon is usually involved in </span>tennis elbow<span>. </span><span>
Medial epicondylitis, or “golfer’s elbow,” is an inflammation of the tendons that attach your forearm muscles to the inside of the bone at your elbow. </span>It's identified by pain from the elbow to the wrist on the inside (medial<span> side) of the elbow. The pain is caused by damage to the tendons that bend the wrist toward the palm.</span>