Fertilizers usually contain two elements from Group 5A, which are

A brick and a feather fall to the earth at their respective terminal velocities. Which objectexperiences the greater force of ai

Karo-lina-s [1.5K]

Answer:

Under the reasonable assumption that the brick has more mass than the feather, the brick experiences a greater force of air friction.

Explanation:

Objects at terminal velocity, only under the influence of gravity, have maximized their speed and have an acceleration of zero. Thus, neither object is accelerating.

Recall Newton's second law: $\sum {\vec {F}}=m \vec {a}$

Since acceleration for each object is zero, the sum of the force acting on each of those objects must also be zero.

Since the only forces acting on the objects are gravity and the force of air friction, in order to zero out, the force of air friction must be equal in magnitude and opposite in direction to the force of gravity.

Recall that near the surface of the earth, $F_{gravity}=mg$ , so the Force of Gravity acting on an object is directly proportional to the object's mass. (A similar argument could be made even if this were not taking place on the surface of the earth, so long as the objects were the same distance from the object providing gravitational influence).

If the masses of the objects are different, the object with the greater mass will experience a larger force of gravity, and hence a larger force of air friction at terminal velocity.

Under the reasonable assumption that the brick has more mass than the feather, the brick experiences a greater force of air friction.

4 0

2 years ago

What is the speed of a wave with a frequency of 6 Hz and a wavelength of 12 m? No links

myrzilka [38]

72 m/s

Explanation:

Given,

Frequency ( f ) = 6 Hz

Wavelength ( λ ) = 12 m

To find : -

Speed ( v ) = ?

Formula : -

v = f x λ

v

= 6 x 12

= 72 m/s

Therefore,

the speed of a wave with a frequency of 6 Hz and a wavelength of 12 m is 72 m/s.

7 0

3 years ago

What is the centripetal force that would be required to keep a 4.0 kg mass moving in a horizontal circle with a radius of 0.80 m

KIM [24]

Answer:

D. 1.8 × 102 newtons radially inward

Explanation:

The magnitude of the centripetal force is given by:

$F=m\frac{v^2}{r}$

where

m is the mass of the object

v is the tangential speed

r is the radius of the circular trajector

In this problem, we have m = 4.0 kg, v = 6.0 m/s and r = 0.80 m, therefore substituting into the equation we get

$F=(4.0 kg)\frac{(6.0 m/s)^2}{0.80 m}=180 N$

The centripetal force is the force that keeps the object in a circular trajectory, so it is a force that is always directed inward (towards the centre of the circular path) and radially. Therefore, the correct answer is

D. 1.8 × 102 newtons radially inward

4 0

4 years ago

Read 2 more answers

A car with a mass of 1.1 × 103 kilograms hits a stationary truck with a mass of 2.3 × 103 kilograms from the rear end. The initi

snow_lady [41]

Answer:

The velocity of the truck after this elastic collision is 15.7 m/s

Explanation:

It is given that,

Mass of the car, $m_1=1.1\times 10^3\ kg$

Mass of the truck, $m_2=2.3\times 10^3\ kg$

Initial velocity of the car, $u_1=22\ m/s$

Initial velocity of the truck, u₂ = 0

After the collision the velocity of the car is, v₁ = -11 m/s

Let v₂ is the velocity of the truck after this elastic collision. Using the conservation of momentum as :

$m_1u_1+m_2u_2=m_1v_1+m_2v_2$

$1.1\times 10^3\times 22+0=1.1\times 10^3\times (11)+2.3\times 10^3\times v_2$

$v_2=15.7\ m/s$

So, the velocity of the truck after this elastic collision is 15.7 m/s. Hence, the correct option is (c).

4 0

3 years ago

Wavelengths of incoming solar radiation are __________________ the wavelengths of reradiated heat. question 2 options: faster th

MArishka [77]

I think that the wavelengths of an incoming solar radiation are shorter than the wavelengths of reradiated heat. This is because the incoming solar radiation to the surface of the earth is in the utraviolet (short) to near infrared (long) wavelength bands. After absorption has taken place, surfaces reradiate heat energy back to the atmosphere at long wavelength infrared.

6 0

3 years ago