Density = (mass) / (volume)
4,000 kg/m³ = (mass) / (0.09 m³)
Multiply each side
by 0.09 m³ : (4,000 kg/m³) x (0.09 m³) = mass
mass = 360 kg .
Force of gravity = (mass) x (acceleration of gravity)
= (360 kg) x (9.8 m/s²)
= (360 x 9.8) kg-m/s²
= 3,528 newtons .
That's the force of gravity on this block, and it doesn't matter
what else is around it. It could be in a box on the shelf or at
the bottom of a swimming pool . . . it's weight is 3,528 newtons
(about 793.7 pounds).
Now, it won't seem that heavy when it's in the water, because
there's another force acting on it in the upward direction, against
gravity. That's the buoyant force due to the displaced water.
The block is displacing 0.09 m³ of water. Water has 1,000 kg of
mass in a m³, so the block displaces 90 kg of water. The weight
of that water is (90) x (9.8) = 882 newtons (about 198.4 pounds),
and that force tries to hold the block up, against gravity.
So while it's in the water, the block seems to weigh
(3,528 - 882) = 2,646 newtons (about 595.2 pounds) .
But again ... it's not correct to call that the "force of gravity acting
on the block in water". The force of gravity doesn't change, but
there's another force, working against gravity, in the water.
Answer:
the acceleration of the car is 1.167 m/s²
Explanation:
Given;
initial velocity of the race car, u = 5 m/s
final velocity of the race car, v = 12 m/s
time to finish the race, t = 6 s
The acceleration of the car is calculated as;
a = (v - u) / t
a = (12 - 5) / (6)
a = 1.167 m/s²
Therefore, the acceleration of the car is 1.167 m/s²
Answer:
If the force on a cart doubles, the acceleration of the cart doubles.
Explanation:
For this problem, we need to consider the following equation:
Force = Mass x Acceleration
We can reasonably assume that the cart will have constant mass in the given force system. With this assumption we can say the following relationship:
Force is directly proportional to Acceleration within the system.
Given that our force on the cart is doubled, then our acceleration of the cart must also be doubled. You can mathematically express this as follows:
F = MA
2F = M * 2A
Hence, if force doubles, the acceleration doubles.
Cheers.
Answer:
Because the wavelengths of macroscopic objects are too short for them to be detectable.
Explanation:
Wavelength of an object is given by de Broglie wavelength as:
Where, 'h' is Planck's constant, 'm' is mass of object and 'v' is its velocity.
So, for macroscopic objects, the mass is very large compared to microscopic objects. As we can observe from the above formula, there is an inverse relationship between the mass and wavelength of the object.
So, for vary larger masses, the wavelength would be too short and one will find it undetectable. Therefore, we don't observe wave properties in macroscopic objects.
