All categories

3 years ago

Formula:

Physics

1 answer:

s2008m [1.1K]3 years ago

8 0

Answer:

55N

Explanation:

Using Newton's second law of motion:

F=ma

Force=mass × acceleration

F=25×2.2

F=55N

So 55 Newtons are needed

You might be interested in

Each of the different colors that make up white light has a different ___________________.

Verdich [7]

Answer:

Wavelength?

Explanation:

7 0

2 years ago

You stand on a bridge above a river and drop a rock into the water below from a height of 25 m. (Assume no air resistance)

Ilia_Sergeevich [38]

PART a)

here when stone is dropped there is only gravitational force on it

so its acceleration is only due to gravity

so we will have

$a = g = 9.8 m/s^2$

Part b)

Now from kinematics equation we will have

$y = v_i t + \frac{1}{2} at^2$

now we have

y = 25 m

so from above equation

$25 = 0 + \frac{1}{2}(9.8 )t^2$

$t = 2.26 s$

Part c)

If we throw the rock horizontally by speed 20 m/s

then in this case there is no change in the vertical velocity

so it will take same time to reach the water surface as it took initially

So t = 2.26 s

Part D)

Initial speed = 20 m/s

angle of projection = 65 degree

now we have

$v_x = vcos\theta$

$v_x = 20 cos65 = 8.45 m/s$

$v_y = vsin\theta$

$v_y = 20 sin65 = 18.13 m/s$

PART E)

when stone will reach to maximum height then we know that its final speed in y direction becomes zero

so here we can use kinematics in Y direction

$v_f - v_y = at$

$0 - 18.13 = (-9.8) t$

$t = 1.85 s$

so it will take 1.85 s to reach the top

5 0

3 years ago

Which property of light remains unchanged when it enters a different medium?

RideAnS [48]

B. Frequency remains unchanged because the energy in a photon is E=hf. So if the frequency changes so does the energy and that doesn't happen to EM waves entering a medium by the conservation of energy

7 0

3 years ago

Read 2 more answers

How to Answer questions 12 and 13

zubka84 [21]

12) The weight of the plane is $7.35\cdot 10^5 N$

13) The lift provided by the wing is $7.35\cdot 10^5 N$

Explanation:

12)

The weight of an object is equal to the force of gravity acting on the object. Near the Earth's surface, it can be calculated as

$W=mg$

where

W is the weight

m is the mass of the object

g is the acceleration of gravity

In this problem, we know that the mass of the plane is

m = 75 tonnes

Since 1 ton = 1000 kg, the mass in kg is

m = 75,000 kg

Also, the acceleration of gravity is

$g=9.8 m/s^2$

Therefore, the weight of the plane is:

$W=(75,000)(9.8)=7.35\cdot 10^5 N$

13)

We can solve this question by applying Newton's second law along the vertical direction of motion. In fact, the net force acting along the vertical direction must be equal to the product between the mass of the plane and the vertical acceleration:

$\sum F_y = ma_y$