All categories

3 years ago

A block has a volume of 0.09 m3 and a density of 4,000 kg/m3. What's the force of gravity acting on the block in water?

2 answers:

5 0

   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.

ratelena [41]3 years ago

5 0

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.

You might be interested in

Resistance training should be performed every day for maximum conditioning benefits.

marysya [2.9K]

Answer:

The answer is True

7 0

3 years ago

Read 2 more answers

How much does Nestle pay the local municipality for access to their spring water?

Lera25 [3.4K]

Around 750 to 1,500.

Hope I helped!

5 0

3 years ago

A college friend of yours who has been postponing taking any science courses hears you talking about the generation of nuclear e

mihalych1998 [28]

Answer:

It's held together by the nuclear force.

Explanation:

There are <em>more</em> elemental forces than just the electromagnetic one. In this case, it is the nuclear force (called also strong force) the one that holds the nucleus together because it is stronger than the electromagnetic force over such short distances as the one inside the atomic nucleus.

8 0

3 years ago

What do electric and magnetic fields have in common?

Nastasia [14]

Electric field, an electric property associated with each point in space when charge is present in any form. The magnitude and direction of the electric field are expressed by the value of E, called electric field strength or electric field intensity or simply the electric field.

Magnetic field are a region around a magnetic material or a moving electric charge within which the force of magnetism acts. Magnetic fields are produced by moving electric charges. Everything is made up of atoms, and each atom has a nucleus made of neutrons and protons with electrons that orbit around the nucleus. Since the orbiting electrons are tiny moving charges, a small magnetic field is created around each atom.

Similarities between magnetic fields and electric fields: Magnetic fields are associated with two magnetic poles, north and south, although they are also produced by charges (but moving charges). Like pole repel unlike poles attract. Electric field points in the direction of the force experienced by a positive charge.

7 0

2 years ago

Ryan is driving home from work and notices a deer leaping onto the road about 25 m in front of his car. He immediately applies t

Anvisha [2.4K]

Answer:

mu = 0.56

Explanation:

The friction force is calculated by taking into account the deceleration of the car in 25m. This can be calculated by using the following formula:

$v^2=v_0^2+2ax\\$

v: final speed = 0m/s (the car stops)

v_o: initial speed in the interval of interest = 60km/h

= 60(1000m)/(3600s) = 16.66m/s

x: distance = 25m

BY doing a the subject of the formula and replace the values of v, v_o and x you obtain:

$a=\frac{v^2-v_o^2}{2x}=\frac{0m^2/s^2-(16.66m/s)^2}{2(25m)}=-5.55\frac{m}{s^2}$

with this value of a you calculate the friction force that makes this deceleration over the car. By using the Newton second's Law you obtain:

$F_f=ma=(1490kg)(5.55m/s^2)=8271.15N$

Furthermore, you use the relation between the friction force and the friction coefficient:

$F_f= \mu N=\mu mg\\\\\mu=\frac{F_f}{mg}=\frac{8271.15N}{(1490kg)(9.8m/s^2)}=0.56$

hence, the friction coefficient is 0.56

6 0

2 years ago