Answer:
(a) The announcer's claim is incorrect because the divers enter at a speed of 20.4 and not 25 m/s as announced
(b) it’s possible for a diver to enter the water with the velocity of 25 m/s if he has initial velocity of 14.4 m/s. The upward initial velocity can’t be physically attained
Explanation:
(a)
To find the final velocity 
for an object traveling distance h taking the initial vertical component of velocity as 
the kinematics equation is written as
where a is acceleration
Substituting g for a where g is gravitational force value taken as 9.81
Since the initial velocity is zero, we can solve for final velocity by substituting figures, note that 70 ft is 21.3 m for h
= 20.44275
Therefore, the divers enter with a speed of 20.4 m/s
The announcer's claim is incorrect because the divers enter at a speed of 20.4 and not 25 m/s as announced
(b)
The divers can enter water with a velocity of 25 m/s only if they have some initial velocity. Using the kinematic equation
Since we have final velocity of 25 m/s
= 14.390761 m/s
Therefore, it’s possible for a diver to enter the water with the velocity of 25 m/5 if he has initial velocity of 14.4 m/s
In conclusion, the upward initial velocity can’t be physically attained
Responder:
A. Ff = 300 N N = 784,8 N
Explicación:
Dado
Masa del cuerpo = 80 kg
Fuerza de movimiento Fm = 300N
Dado que el cuerpo no está acelerando, la fuerza de fricción (Ff) es igual a la fuerza de movimiento que actúa sobre el cuerpo, ya que la fuerza de fricción es una fuerza de oposición, es decir, Fm = Ff
Dado que Fm = 300N, Ff = 300N
La reacción normal que actúa en el cuerpo es igual al peso.
N = W = mg
g es la aceleración debida a la gravedad
g = 9,8 m / s
N = mg
N = 80 (9,81)
N = 784,8N
Por tanto, la fuerza normal que actúa sobre el cuerpo es 784,8 N
40 miles/hour
Details:
after one hour they have traveled 40mi. So they have traveled 40mi. in 1hr, or 40mi/1hr or 40mi/hr.
the problem is about reading a graph. the graph says that they traveled 40 miles in the first hour
formula for average speed:
miles traveled/time it took=speed or d/t=r
Answer:
Explanation:
Acceleration is the rate of change of velocity. Usually, acceleration means the speed is changing, but not always. When an object moves in a circular path at a constant speed, it is still accelerating, because the direction of its velocity is changing.
