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3 years ago

3.

Physics

2 answers:

Alborosie3 years ago

4 0

Answer:

Explanation:

Acceleration is defined as a change in velocity over time. This means that as long as the forces are not zero, the velocity should be changing. The can be negative (as this is negative acceleration also known as deceleration) or positive (known as acceleration). It doesn't matter if they are decimals or fractions.

Nookie1986 [14]3 years ago

4 0

In order for acceleration of an object to occur, the sum of the forces must be anything but zero.

Answer: Option C

<u>Explanation: </u>

Based on Newton second laws of motion, the acceleration due to gravity of any object is directly proportional to the net force acting on the object and inversely proportional to the mass of the object. So, the sum of all the forces acting on the object will decide the acceleration attained by the object.

If the total forces are zero then the acceleration of the object will be zero. In case of deceleration, the net force would be having negative sign and thus increase in net force will lead to increase in acceleration. Hence, for the occurrence of acceleration, the total forces sum would be anything but zero.

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50 points!!! Kinetics

iris [78.8K]

Answer:

98 m √

Explanation:

How about s = Vo * t + ½at² ?

s = h = Vo * 2s - 4.9m/s² * (2s)² = 2Vo - 19.6

and

h = Vo * 10s - 4.9m/s² * (10s)² = 10Vo - 490

Subtract 2nd from first:

0 = -8Vo + 470.4

Vo = 58.8 m/s

h = 58.8m/s * 2s - 4.9m/s² * (2s)² = 98 m

3 0

3 years ago

Read 2 more answers

______ can occur when water-saturated soil turns from a solid to a liquid as a result of an earthquake.

jek_recluse [69]

The answer is liquefaction

6 0

2 years ago

A 3.8kw elective motor powers an inclined conveyer belt. It is designed to lift heavy boxes from the warehouse floor to loading

zhannawk [14.2K]

Answer:

See the answers below

Explanation:

To solve this problem we must use the definition of power and work in physics.

The function of the conveyor belt is to carry the boxes from an initial point that is at low altitude to an end point that is at high altitude. In this way the conveyor belt prints a speed to the box to be able to raise it to the required vertical distance.

Since we have a velocity at the beginning and then we place the box at a high position, where then the box remains at rest, we can say that it converts kinetic energy to potential energy.

Power is defined as the relationship of work over time. Therefore we have:

$P=W/t$

where:

P = power = 3.8 [kW] = 3800 [W]

W = work [J]

t = time = 14 [s]

$W=P*t\\W=3800*14\\W= 53200[J] = 53.2[kJ]$

Since the given time is equal to the given time at Point b, we can use the same work calculated.

We know that work is defined as the product of force by the distance traveled.

$W =F*d$

So, the force is equal to:

$F=W/d\\F=53200/5.3\\F=10037.73[N]$

Now we know that force is defined as the product of mass by gravitation acceleration.

$F =m*g$

where:

F = force or weight = 10037.73 [N]

g = gravity acceleration = 9.81 [m/s²]

m = mass [kg]

$m=F/g\\m = 10037.73/9.81\\m = 1023.2 [kg]$

This part can be solved by means of the energy conservation theorem, where the potential energy is transformed into kinetic energy or vice versa.

$E_{pot}=m*g*h = E_{kin}=0.5*m*v^{2}$

where:

h = elevation = 4.7 [m]

v = velocity [m/s]

$m*g*h=0.5*m*v^{2}\\g*h=0.5*v^{2} \\v=\sqrt{\frac{g*h}{0.5} } \\v=\sqrt{\frac{9.81*4.7}{0.5} } \\v = 9.6 [m/s]$

7 0

3 years ago

The following is the longitudinal characteristic equation for an F-89 flying at 20,000 feet at Mach 0.638. The Short Period natu

BartSMP [9]

Answer:

hello your question is incomplete attached below is the missing part

answer : short period oscillations frequency = 0.063 rad / sec

phugoid oscillations natural frequency ( $w_{np}$ ) = 4.27 rad/sec

Explanation:

first we have to state the general form of the equation

= $( S^2 + 2\alpha _{p} w_{np} S + w^{2} _{np} ) (S^{2} + 2\alpha _{s} w_{ns}S + w^{2} _{ns} ) = 0$

where :

$w_{np} = Natural frequency of plugiod oscillation$

$\alpha _{p} = damping ratio of plugiod oscilations$

comparing the general form with the given equation

$w^{2} _{np}$ = 18.2329

$w^{2} _{ns} = 0.003969$

hence the short period oscillation frequency ( $w_{ns}$ ) = 0.063 rad/sec

phugoid oscillations natural frequency ( $w_{np}$ ) = 4.27 rad/sec

8 0

3 years ago

Firecrackers A and B are 600 m apart. You are standing exactly halfway between them. Your lab partner is 300 m on the other side

pishuonlain [190]

Answer:

See the explanation

Explanation:

Given:

Distance of Firecrackers A and B = 600 m

Event 1 = firecracker 1 explodes

Event 2 = firecracker 2 explodes

Distance of lab partner from cracker A = 300 m

You observe the explosions at the same time

to find:

does event 1 occur before, after, or at the same time as event 2?

Solution:

Since the lab partner is at 300 m distance from the firecracker A and Firecrackers A and B are 600 m apart

So the distance of fire cracker B from the lab partner is:

600 m + 300 m = 900 m

It takes longer for the light from the more distant firecracker to reach so

Let T1 represents the time taken for light from firecracker A to reach lab partner

T1 = 300/c

It is 300 because lab partner is 300 m on other side of firecracker A

Let T2 represents the time taken for light from firecracker B to reach lab partner

T2 = 900/c

It is 900 because lab partner is 900 m on other side of firecracker B

T2 = T1

900 = 300

900 = 3(300)

T2 = 3(T1)

Hence lab partner observes the explosion of the firecracker A before the explosion of firecracker B.

Since event 1 = firecracker 1 explodes and event 2 = firecracker 2 explodes

So this concludes that lab partner sees event 1 occur first and lab partner is smart enough to correct for the travel time of light and conclude that the events occur at the same time.

8 0

3 years ago