Permeability is the condition of being capable of having materials flow into and out of a membrane. The permeability of a cell membrane is determined by how easily a molecule can diffuse across the membrane. Usually, only molecules that are fat-soluble can permeate across a cell membrane. This is because the layer that is exposed on the linings of the cell membrane is nonpolar and can therefore allow the fat-soluble molecule to pass through.
Answer:Cell membranes are composed of a lipid bilayer.
Explanation:
Answer: The average velocity will be 0 m/s.
Explanation:
Average velocity is defined as the fraction of displacement and total time.
In the given question, it states that the person stops at the same point from where it started, which means that the displacement of this person is 0 meters.
Therefore, the average velocity becomes:
Hence, the average velocity will be 0 m/s.
Answer:
doppler effect
Explanation:
When the relative motion of two bodies results in the wavelength becoming shorter this means that the bodies are getting closer. This is known as blue shift.
When the relative motion of two bodies results in the wavelength becoming longer this means that the bodies are getting farther. This is known as red shift.
Collectively this phenomenon is known as the Doppler effect.
Answer:
Explanation:
Given
Kinetic energy varies jointly as mass and square of velocity
for
for
Divide 1 & 2 we get
Kinetic energy is proportional to mass and the square of velocity. It can be calculated for different masses and velocities using a constant derived from specific known values.
The principle of kinetic energy states that kinetic energy is directly proportional to mass and the square of velocity. Therefore, we can use the equation Kinetic Energy = 0.5 * Mass * Velocity^2 to calculate kinetic energy.
In this example, a mass of 15 grams and a velocity of 3 cm/s generates a kinetic energy of 27 ergs. By this equation, we derive a constant K. For a mass of 5 grams and a velocity of 9 cm/s, we can easily find the kinetic energy using this K value and multiplying it with the given mass and the square of the velocity.
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The gravitational force acting on a 70.0 kg object on Earth is calculated using the formula w=mg and is equal to 686 N.
The gravitational force acting on a 70.0 kg object standing on the earth's surface can be calculated using the formula for weight (which is essentially the gravitational force on the object): w = mg, where m is the mass of the object and g is the acceleration due to gravity. On Earth, g is approximately 9.8 m/s².
Therefore, the gravitational force (weight) acting on this object can be calculated as follows: w = mg = (70.0 kg)(9.8 m/s²) = 686 N. Thus, the gravitational force on this 70.0 kg object standing on the earth's surface is 686 Newtons. It's important to understand that this force will vary if the object is moved to a location where g is different, like on the moon.
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Express your answer to two significant figures and include the appropriate units.
Answer:
Explanation:
given,
Speed of sound = 343 m/s
frequency of horn = 260 Hz
the friend is approaching, the frequency is increased by the Doppler Effect. The frequency is 266 Hz
using formula
the speed of friends approaching is equal to