What is the original source of the energy stored in fossil fuels?

A bullet of mass 6.20 10-3 kg, moving at 1320 m/s impacts a tree stump and penetrates 11.00 cm into the wood before coming to re

sladkih [1.3K]

Answer:

F = -49.1 10³ N

Explanation:

Let's use the kinematics to find the acceleration the acceleration of the bullet that they tell us is constant

$v_{f}$ ² = v₀² + 2 a x

Since the bullet is at rest, the final speed is zero

x = 11.00 cm (1 m / 100 cm) = 0.110 m

0 = v₀² + 2 a x

a = -v₀² / 2 x

a = -1320²/(2 0.110)

a = -7.92 10⁶ m / s²

With Newton's second law we find the force

F = m a

F = 6.20 10⁻³ (-7.92 10⁶)

F = -49.1 10³ N

The sign means that it is the force that the tree exerts to stop the bullet

8 0

2 years ago

What is the mathematical relationship between wavelength and velocity?

gavmur [86]

Answer:A wave has a wavelength λ, which is the distance between adjacent identical parts of the wave. The wave velocity and the wavelength are related to the wave's frequency and period by vw=λT or vw=fλ.

Explanation:

8 0

2 years ago

The two equal strong kids are having a tug a war. What do you expect to happen to the ball in this situation

borishaifa [10]

Answer:as per as Newtons second law, The forces exerted on the rope create tension.

As such,The tension is equal to the applied force.The tension is trasmitted to the opposite side and of the rope delivering the applied force.

Hope this helps.. :)

3 0

2 years ago

Which statement explains how it is possible to carry books to school without changing the kinetic or potential energy of the boo

Mamont248 [21]

Answer:

a. by moving the book without acceleration and keeping the height of the book constant

Explanation:

FOR CONSTANT KINETIC ENERGY:

The kinetic energy of a body depends upon its speed according to its formula:

ΔK.E = (1/2)mΔv²

So, for Δv = 0 m/s

ΔK.E = 0 J

So, for keeping kinetic energy constant, the books must be moved at constant speed without acceleration.

FOR CONSTANT POTENTIAL ENERGY:

The potential energy of a body depends upon its height according to its formula:

ΔP.E = mgΔh

So, for Δh = 0 m/s

ΔP.E = 0 J

So, for keeping potential energy constant, the books must be moved at constant height.

So, the correct option is:

<u>a. by moving the book without acceleration and keeping the height of the book constant</u>

8 0

2 years ago

A uniform magnetic field is perpendicular to the plane of a circular loop of diameter 13 cm formed from wire of diameter 2.6 mm

I am Lyosha [343]

Answer:

Rate of change of magnetic field is $3.466\times 10^3T/sec$

Explanation:

We have given diameter of the circular loop is 13 cm = 0.13 m

So radius of the circular loop $r=\frac{0.13}{2}=0.065m$

Length of the circular loop $L=2\pi r=2\times 3.14\times 0.065=0.4082m$

Wire is made up of diameter of 2.6 mm

So radius $r=\frac{2.6}{2}=1.3mm=0.0013m$

Cross sectional area of wire $A=\pi r^2=3.14\times0.0013^2=5.30\times 10^{-6}m^2$

Resistivity of wire $\rho =2.18\times 10^{-8}m$

Resistance of wire $R=\frac{\rho L}{A}=\frac{2.18\times 10^{-8}\times 0.4082}{5.30\times 10^{-6}}=1.67\times 10^{-3}ohm$

Current is given i = 11 A

So emf $e=11\times 1.67\times 10^{-3}=0.0183volt$

Emf induced in the coil is $e=-\frac{d\Phi }{dt}=-A\frac{dB}{dt}$

$0.0183=5.30\times 10^{-6}\times \frac{dB}{dt}$

$\frac{dB}{dt}=3.466\times 10^3=T/sec$

8 0

2 years ago