Answer:
D)Not enough information
Explanation:
According to Pascal's principle, the pressure exerted on the two pistons is equal:
Pressure is given by the ratio between force F and area A, so we can write
The force exerted on each piston is just equal to the weight of the corresponding mass: , where m is the mass and g is the gravitational acceleration. So the equation becomes
Now we can rewrite the mass as the product of volume, V, times density, d:
We also know that
So we can further re-arrange the equation (and simplify g as well):
We are also told that block B has bigger volume than block A: . However, this information is not enough to allow us to say if the fraction on the right is greater than 1 or smaller than 1: therefore, we cannot conclude anything about the densities of the two objects.
Answer:
the velocity is zero, the acceleration is directed downward, and the force of gravity acting on the ball is directed downward
Explanation:
Is this exercise in kinematics
v = v₀ - g t
where g is the acceleration of the ball, which is created by the attraction of the ball to the Earth.
At the highest point
velocity must be zero.
The acceleration depends on the Earth therefore it is constant at this point and with a downward direction.
The force of the earth on the ball is towards the center of the Earth, that is, down
all other alternatives are wrong
C is a non-metal and so is O. So the answer is CO
The equivalent of the Newton's second law for rotational motions is:
where
is the net torque acting on the object
is its moment of inertia
is the angular acceleration of the object.
Re-arranging the formula, we get
and since we know the net torque acting on the (vase+potter's wheel) system,
, and its angular acceleration,
, we can calculate the moment of inertia of the system:
Answer: D
Explanation: read the answers above and compare to your test