In a pendulum system, when is it possible for the potential and kinetic energies both to be equal to zero

1. The horizontal and vertical components of a projectile's velocity are

Anni [7]

The horizontal and vertical components of a projectile's velocity are independent of each other.

Answer: Option C

Explanation:

The path of a projectile is determined by two components of motion. They are termed as horizontal and the vertical components. Since both components velocity are perpendicular to each other, so it can stated that they are independent of each other.

Even it can seen that when the horizontal components of velocity is constant, then there will be change in the vertical components of velocity leading to free fall projectile path.

And in the absence of gravity, there will be change in the horizontal components of velocity with zero vertical component of velocity. Thus, the horizontal and the vertical components of a projectile’s velocity are seemed to be independent of each other.

5 0

3 years ago

In the Daytona 500 auto race, a Ford Thunderbird and a Mercedes Benz are moving side by side down a straightaway at 71.0 m/s. Th

elena55 [62]

Answer:

Thunderbird is 995.157 meters behind the Mercedes

Explanation:

It is given that all the cars were moving at a speed of 71 m/s when the driver of Thunderbird decided to take a pit stop and slows down for 250 m. She spent 5 seconds in the pit stop.

Here final velocity $v=0 \ m/s$

initial velocity $u= 71 m/s$ distance

Distance covered in the slowing down phase = $250 m$

$v^2-u^2=2as$

$a= \frac {(v^2-u^2)}{2s}$

$a = \frac {(0^2-71^2)}{(2 \times 250)}=-10.082 \ m/s^2$

$v=u+at$

$t= \frac {(v-u)}{a}$

$= \frac {(0-71)}{(-10.082)}=7.042 s$

$t_1=7.042 s$

The car is in the pit stop for 5s $t_2=5 s$

After restart it accelerates for 350 m to reach the earlier velocity 71 m/s

$a= \frac {(v^2-u^2)}{(2\times s)} = \frac{(71^2-0^2)}{(2 \times 370)} =6.81 \ m/s^2$

$v=u+at$

$t= \frac{(v-u)}{a}$

$t= \frac{(71-0)}{6.81}= 10.425 s$

$t_3=10.425 s$

total time= $t_1 +t_2+t_3=7.042+5+10.425=22.467 s$

Distance covered by the Mercedes Benz during this time is given by $s=vt=71 \times 22.467= 1595.157 m$

Distance covered by the Thunderbird during this time= $250+350=600 m$

Difference between distance covered by the Mercedes and Thunderbird

= $1595.157-600=995.157 m$

Thus the Mercedes is 995.157 m ahead of the Thunderbird.

6 0

3 years ago

4. An electric iron has a

Licemer1 [7]

Answer:

4.

a) W = 750 J

b) W = 2250 J

c) t = 2 sec

5. Answered in explanation

Explanation:

4.

The formula of power is given as:

P = W/t

where,

P = Power

W = Work Done

t = Time Taken

a)

Here,

P = 750 W

t = 1 sec

W = ?

Therefore,

750 W = W/1 sec

W = 750 J

b)

Here,

P = 750 W

t = 3 sec

W = ?

Therefore,

750 W = W/3 sec

W = (750 W)(3 sec)

W = 2250 J

c)

Here,

P = 750 W

t = ?

W = 1500 J

Therefore,

750 W = 1500 J/t

t = 1500 J/750 W

t = 2 sec

5.

According to Kinetic Particle Theory, the molecules are tightly packed with each other, by strong inter-molecular forces and they can only vibrate at their position. While, molecules or particles in liquids have lesser attractive forces among them. They can move in layers and can take the shape of any container. This is the reason why solid has a definite shape and liquid has none.

6 0

3 years ago

Molly is looking for a sustainable fuel source that doesn't require technical equipment to harness. She is concerned that trees

notka56 [123]

Answer:

She can consider using agricultural waste or dried dung.

Explanation:

No doubt, biomass has become a crucial source of energy to the society, with almost 90% of the households in rural area now relying on biomass for energy. Biomass has become a great option for household heating and cooking. It is locally available and abundant. It is a clean type of fuel, unlike fossil fuels and it somehow helps in cleaning our environment as it traps carbondioxide. Some common types of biomass include dried dung, agricultural waste, or even charcoal.

8 0

3 years ago

Read 2 more answers

How do you find the net force acting on an object?

weqwewe [10]

Answer:

C. Add all the force vectors

Explanation:

The net force acting on an object is the vector sum of all the forces on the object.

Remember, Newton's first law tells us a body at rest will remain at rest or that in uniform motion will continue in motion unless acted by unbalanced forces.These unbalanced forces act in all direction towards the body thus to get the net force you require a summation of all these force with respect to their magnitudes and directions.

For example a force of 3N towards the East direction acting on a body and another force of 2N towards the West direction on the same body will generate a net force of 1N towards the East direction.

4 0

3 years ago