Answer:
The time taken by the brick to hit the ground, t = 0.84 s
Explanation:
Given that,
A brick falls from a height, h = 3.42 m
The initial velocity of the brick is zero.
Since the brick is under free-falling. The time equation of a free-falling body when the displacement is given is
t = 
where,
h - height from surface in meters
g - acceleration due to gravity
on substituting the values in the above equation,
t = 
= 0.84 s
Hence, time taken by the brick to hit the ground is t = 0.84 s
Answer:
The work done on the box is 100 Nm
The power is 20 Nm/s
Explanation:
There is a force 25 newtons moves a box a distance of 4 meters in
5 seconds
The work done on the box is the product of the force and the distance
that the box moves ⇒ <em>work = force × distance</em>
The force = 25 newtons
the distance = 4 meters
Work = 25 × 4 = 100 NM
<em>The work done on the box is 100 Nm</em>
<em></em>
The force moves the box 4 meters in 5 seconds
The power is the rate of work
<em>The power = work ÷ time</em>
The work = 100 Nm
The time = 5 seconds
The power = 100 ÷ 5 = 20 Nm/s
<em>The power is 20 Nm/s</em>
Refer to the figure shown below.
Let m₁ and m₂ e the two masses.
Let a = the acceleration.
Let T = tension over the frictionless pulley.
Write the equations of motion.
m₂g - T = m₂a (1)
T - m₁g = m₁a (2)
Add equations (1) and (2).
m₂g - T + T - m₁g = (m₁ + m₂)a
(m₂ - m₁)g = (m₁ + m₂)a
Divide through by m₁.
(m₂/m₁ - 1)g = (1 + m₂/m₁)a
Define r = m₂/m₁ as the ratio of the two masses. Then
(r - 1)g = (1 +r)a
r(g-a) = a + g
r = (g - a)/(g + a)
With = 2 ft/s from rest, the acceleration is
a = 2/32.2 = 0.062 ft/s²
Therefore
r = (32.2 - 0.062)/(32.2 + 0.062) = 0.9962
Answer:
The ratio of masses is 0.9962 (heavier mass divided by the lighter mass).
<span>Good Morning!
The scientific advance that launched an ethical alert in the scientific community was the possibility of cloning animals, since it presents important questions, especially if such a project is extended to humans.
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