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3 years ago

Why is acceleration negative in a free fall?

2 answers:

6 0

Technically speaking altitude is measured from the ground up.
Therefore, say you're falling from 1000 metres, that number decreases till it reaches 0. Therefore, you're accelerating but towards the ground i.e. towards 0.

Therefore acceleration is negative because you're travelling at -x metres per second and accelerating at -x metres per second^2

murzikaleks [220]3 years ago

5 0

Only because when most people work with vertical motion, they call the upward direction positive. So falling objects have negative velocity and acceleration. But if you prefer to call the downward direction positive, you have every right to do that. Then the force of gravity on a falling object, as well as its velocity and acceleration, are all positive, and its negative altitude steadily grows until it hits the ground.

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Please help<br> types of stimuli the sensory organs receive.

Alborosie

Answer: Photoreceptor cell, Chemoreceptor, Thermoreceptor, Mechanoreceptor

Hope this helps(:

Explanation:

3 0

2 years ago

After driving a portion of the route, the taptap is fully loaded with a total of 27 people including the driver, with an average

lara [203]

Answer:

compression of spring is x = 0.12 m

Assumed k = 160,000 N/m ........ Truck's suspension system

Explanation:

Given:

- The mass of average person m_p = 69 kg

- Total number of persons n_p = 27

- The mass of each goat m_g = 15 kg

- The total number of goats n_g = 3

- The mass of each chicken m_c = 3 kg

- The total number of goats n_c = 5

- The total mass of bananas m_b = 25 kg

Find:

How much are the springs compressed?

Solution:

- Using equilibrium equation on the taptap in vertical direction:

F_net = F_spring - F_weight = 0

- Compute the force due to all the weights on the taptap:

F_weight = (n_p*m_p + n_g*m_g + n_c*m_c + m_b)*9.81

F_weight = (69*27 + 3*15 + 5*3 + 25)*9.81

F_weight = 19109.88 N

- The restoring force of a spring is given by:

F_spring = k*x

Where, k is the spring stiffness and x is the displacement:

F_weight = F_spring

19109.88 = k*x

x = 19109.88 / k

We need to assume the spring stiffness we will take k = 160,0000 N/m (trucks suspension systems). The value of the stiffness must be high enough to sustain a load of 1.911 tonnes.

x = 19109.88 / 160,000

x = 0.1194 m ≈ 0.12 m = 12 cm

- A compression of 12 cm seems reasonable for a taptap to carry 1.911 tonnes of load. Hence, the assumption of spring stiffness was reasonable. Hence, the compression of spring is x = 0.12 m.

8 0

3 years ago

A mason is shot with a constant speed of 7.5 x 10²m/sinto a region, when an electric field produces acceleration on the mason of

nadya68 [22]

Answer:

Distance, d = 0.1 m

It is given that,

Initial velocity of meson,

Finally, the meson is coming to rest v = 0

Acceleration of the meson, (opposite to initial velocity)

Using third equation of motion as :

s is the distance the meson travelled before coming to rest.

So,

s = 0.1 m

The meson will cover the distance of 0.1 m before coming to rest. Hence, this is the required solution.

5 0

2 years ago

Assortative mating changes ______ frequencies but does not change ______ frequencies.

andrew-mc [135]

Allele frequencies are unaffected by assortative mating, but genotype frequencies .

<h3>Assortative mating: </h3>

Individuals with similar phenotypes and genotypes mate with others more frequently than is anticipated under a random mating pattern in assortative mating, which is a mating pattern and a type of sexual selection.

<h3>Frequencies of genotypes:</h3>

A population's genotype frequency is calculated by dividing the number of people having a particular genotype by the overall population size. The genotype frequency in population genetics is the frequency or ratio (i.e., 0 f 1) among genotypes inside a population.

<h3>The frequency for alleles in biology:</h3>

The term "allele frequency" describes the prevalence of an allele in a population. It is calculated by calculating the number of times the allele occurs in the population and dividing by the sum of all the gene copies.

To know more about Assortative mating visit:

brainly.com/question/28238408

#SPJ4

4 0

1 year ago

A rubber ball is dropped from a height of 8m. After strikingthe floor, the ball bounces to a height of 5m. a. If the ball had bo

kifflom [539]

Answer:

a) This means the collision between the ball and the floor is elastic.

b) This points to a perfectly inelastic collision between the ball and the floor as they stick together after collision

c) Check Explanation.

Explanation:

Collision of bodies are analysed according to whether both momentum and kinetic energy of the system is conserved, that is, if these two quantities before collision are equal to their values after collision.

In all types of collisions, momentum is usually conserved, but kinetic energy is conserved only in an elastic collision.

A ball dropped from a height of 8 m bounces up back to a height of 5 m.

a. If the ball had bounced to a height of 8m, how would you describe the collision between the ball and the floor?

The ball not bouncing back to a height of 8 m shows energy loss at some point in the total motion of the ball (most likely at the collision). If kinetic energy was conserved, the ball would bounce back up to the height at which it fell from (8 m) after the collision with the floor.

b. If the ball had not bounced at all, how would you describe the collision between the ball and the floor?

If the ball had not bounced at all, this means it lost all of its kinetic energy to the floor, and this points to a perfectly inelastic collision between the ball and the floor as they stick together after collision.

c. What happened to the energy lost by the ball during thecollision?

The energy lost during the collision is converted to another form, most likely responsible for some deformation on the ball & a minute deformation on the floor, converted to some form of heat as a result of the collision or into sound energy, usually, it's a combination of all This!

Hope this Helps!!!

5 0

3 years ago