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3 years ago

Choose whether each of the following statements is true or false

Physics

1 answer:

kow [346]3 years ago

6 0

Answer:

1. The statement is false.

2. The statement is false.

Explanation:

1. When a ball is thrown vertically up, the air drag is acting downwards which reduces the time the ball spends traveling upwards, but the air drag is acting upwards while the ball is falling, which increases the time the ball spends traveling downwards.

Thus, the statement is false.

2. The potential energy of a particle is given by

$V = mgh$

where, $m$ is the mass of the object, $g$ is the acceleration due to gravity and $h$ is the vertical height traveled by the object.

It does not depend on th initial velocity of the object.

Thus, the statement is false.

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1.How long dose long term alcohol abuse affect the liver ?

Agata [3.3K]

1. B- it can cause cirrhosis
2. C- intoxication
3. A- admit to having a problem with alcohol
4. D- binge-drinking
5. A- depressant
6. true
7. false

7 0

2 years ago

Read 2 more answers

A 0.290 kg potato is tied to a string with length 2.50 m, and the other end of the string is tied to a rigid support. The potato

Sergeu [11.5K]

Answer:

A) The speed of the potato at the lowest point of its motion is 7.004 m/s

B) The tension on the string at this point is 8.5347 N

Explanation:

Here we have that the height from which the potato is allowed to swing is 2.5 m

Therefore we have ω₂² = ω₁² + 2α(θ₂ - θ₁)

Where:

ω₂ = Final angular velocity

ω₁ = Initial angular velocity = 0 rad/s

α = Angular acceleration

θ₂ = Final angle position

θ₁ = Initial angle position

However, we have potential energy of the potato

= Mass m×Gravity g× Height h

= 0.29×9.81×2.5 = 7.1125 J

At he bottom of the swing, the potential energy will convert to kinetic energy as follows

K.E. = P.E. = 7.1125 J

1/2·m·v² = 7.1125 J

Therefore,

v² = 7.1125 J/(1/2×m) = 7.1125 J/(1/2×0.290) = 49.05

∴ v = √49.05 = 7.004 m/s

B) Here we have the tension given by

Tension T in the string = weight of potato + Radial force of motion

Weight of potato = mass of potato × gravity

Radial force of motion of potato = mass of potato × α,

where α = Angular acceleration = v²/r and r = length of the string

∴ Tension T in the string = m×g + m×v²/r = 0.290×(9.81 + 7.004²/2.5)

T = 8.5347 N

4 0

3 years ago

Read 2 more answers

Which one of the following is a decomposition reaction?

BabaBlast [244]

You would know a decomposition reaction occurred if the reactants separated. For example from AB → A+B.

Now if you look at your options only 1 works out for that equation. Letter A.
From the compound K2CO3 it split up to K2O +CO2

It cannot be letter B because synthesis/combination occurred. The same goes for letter C. Letter D, single displacement occurred.

Again, the answer is A.

4 0

3 years ago

Rahul has 2 bulbs connected across two cells in a simple circuits shown. How can he make the bulbs glow dimmer?

Ray Of Light [21]

Answer:

in the parallel connection the light bulbs shine less than in the series connection

Explanation:

In a series circuit the current through the whole circuit is the same, therefore the power (brightness) of each bulb is

P = i² R

where R is the resistance of each bulb and i the current of the circuit.

If we connect the light bulbs and the cells in parallel, the current in the circuit is the sum of the east that passes through each light bulb,

i = i₁ + i₂

if the two light bulbs are the same

i = 2 i₁

i₁ = i / 2

so the power of each bulb is is

P = i₁² R

P = R i² / 4

P = ¼ P_initial

Therefore we see that in the parallel connection the light bulbs shine less than in the series connection

3 0

2 years ago

What happens to the open circuit if a small fan is connected at point f and the circuit is closed

liraira [26]

There's no way to tell. Without seeing a diagram of the circuit,
I'll need to know much more about it than you've told me.
I don't know anything about the components or power supply
that are in the circuit, and I don't know where point ' f ' is in it.

Right now, even with the copious volume of all the available
information, no answer to your question is possible.

4 0

3 years ago