Answer:
a) 5200 N b) 8800 N
Explanation:
a) tension in the cable when it was being lowered to the sea floor = weight of the object which acts downward ( equals the tension in the cable when the craft was stationary in opposite direction) - the drag force which will act upward = 7000 - 1800 = 5200 N
b) tension in the cable when the craft was being raised since the tension will act upward and the drag force and the weight will act downward = 7000 + 1800 = 8800 N
The correct answer to the question is : D) Impulse
EXPLANATION:
Before going to answer this question, first we have to understand impulse.
Impulse of a body is defined as change in momentum or the product of force with time.
Mathematically impulse = F × t = m ( v - u ).
Here, v is the final velocity
u is the initial velocity
F is the force acting on the body for time t.
Hence, the perfect answer of this question is impulse m i.e the force multiplied with time is known as impulse.
Answer:
mesuring heigh and weight is important
Answer:
The options are not shown, so let's derive the relationship.
For an object that is at a height H above the ground, and is not moving, the potential energy will be:
U = m*g*H
where m is the mass of the object, and g is the gravitational acceleration.
Now, the kinetic energy of an object can be written as:
K = (1/2)*m*v^2
where v is the velocity.
Now, when we drop the object, the potential energy begins to transform into kinetic energy, and by the conservation of the energy, by the moment that H is equal to zero (So the potential energy is zero) all the initial potential energy must now be converted into kinetic energy.
Uinitial = Kfinal.
m*g*H = (1/2)*m*v^2
v^2 = 2*g*H
v = √(2*g*H)
So we expressed the final velocity (the velocity at which the object impacts the ground) in terms of the height, H.
