I need help with question 6 and 7!!! Also, how to do the back???

During take-off a 5kg model rocket, initially at rest, burns fuel for 4.6s causing its speed to increase from rest to 39m/s duri

MrRa [10]

Answer:

The height is "89.61 m". A further explanation is given below.

Explanation:

According to the question,

Mass of rocket,

m = 5 kg

Time,

t = 4.6 s

Initial speed of rod

u = o m/s

Final speed,

v = 39 m/s

drag,

= 60 N

So,

⇒ acceleration, $a=\frac{v-u}{t}$

$=\frac{39-0}{4.6}$

$= 8.478 \ m/s^2$

⇒ $F_{net}= Net \ force$

$=ma$

$=5\times 8.478$

$=42.89 \ N$

Now,

The thrust will be:

⇒ $Thrust-weight-drag=Net \ force$

⇒ $Thrust-(5\times 9.8)-60=42.89$

⇒ $Thrust-49-60=42.89$

⇒ $Thrust-109=42.89$

⇒ $Thrust=42.89+109$

⇒ $Thrust=151.89 \ N$

The height will be:

⇒ $h=\frac{1}{2} at^2$

$=\frac{1}{2}\times 8.47\times (4.6)^2$

$=\frac{1}{2}\times 8.47\times 21.16$

$=89.61 \ m$

5 0

2 years ago

Who was th efirst person to come up with the idea of the atoms.

Gwar [14]

Answer:

Democritus

Explanation:

Democritus was a Greek philosopher who was the first person to use the term atom . However ,John Dalton was the first to adapt Democritus’ theory into the first modern atomic

model

7 0

2 years ago

The main advantage banking services offer is?

KATRIN_1 [288]

In short, and in general:

Advantages

Credit Unions typically pay higher dividend rates on savingsCredit Unions typically offer lower rates on loansCredit Unions typically provide better service; since they are owned and governed by their membership, they tend to prioritize the needs of their members above all elseCredit Unions operate on a not-for-profit business model, so excess earnings are returned back to the membership in form of competitive rates and lower fees, and sometimes even special dividendsMany Credit Unions offer the same products and services found at banksCredit Unions often have added-value benefits, such as free financial education, discounted theme park tickets, and special member rates for services such as home alarm systems...even discounts at online retailers like Barnes & Noble.Disadvantages

Credit Unions, and in particular smaller local credit unions, struggle to match the level of convenience (ATMs and branches) that many banks provide their customers, although many CUs are part of shared networks which enhance the breadth of delivery channels available to their membersSome Credit Unions are limited in their product offeringsOne must qualify for membership One must pay a membership fee to join. hope this helps!

7 0

2 years ago

A rod of length L and electrical resistance R moves through a constant uniform magnetic field ; both the magnetic field and the

CaHeK987 [17]

Answer:

don't know what class are you you are using which mobile or laptop

6 0

2 years ago

A toy rocket, launched from the ground, rises vertically with an acceleration of 28 m/s 2 for 9.7 s until its motor stops. Disre

vredina [299]

Answer:

5080.86m

Explanation:

We will divide the problem in parts 1 and 2, and write the equation of accelerated motion with those numbers, taking the upwards direction as positive. For the first part, we have:

$y_1=y_{01}+v_{01}t+\frac{a_1t^2}{2}$

$v_1=v_{01}+a_1t$

We must consider that it's launched from the ground ( $y_{01}=0m$ ) and from rest ( $v_{01}=0m/s$ ), with an upwards acceleration $a_{1}=28m/s^2$ that lasts a time t=9.7s.

We calculate then the height achieved in part 1:

$y_1=(0m)+(0m/s)t+\frac{(28m/s^2)(9.7s)^2}{2}=1317.26m$

And the velocity achieved in part 1:

$v_1=(0m/s)+(28m/s^2)(9.7s)=271.6m/s$

We do the same for part 2, but now we must consider that the initial height is the one achieved in part 1 ( $y_{02}=1317.26m$ ) and its initial velocity is the one achieved in part 1 ( $v_{02}=271.6m/s$ ), now in free fall, which means with a downwards acceleration $a_{2}=-9,8m/s^2$ . For the data we have it's faster to use the formula $v_f^2=v_0^2+2ad$ , where d will be the displacement, or difference between maximum height and starting height of part 2, and the final velocity at maximum height we know must be 0m/s, so we have: