Help..... disregard my answers...plz help

A discus thrower achieves a high throw of 100m with the discus released at an angle of 30° calculate the initial speed of the di

GaryK [48]

Answer:

u = 88.54 m/s

Explanation:

Given that,

A discus thrower achieves a high throw of 100 m.

Angle of projection is 30°

We need to find the initial speed of the discuss. It is a cse of projectile motion. The maximum height reached by the discus is given by :

$H=\dfrac{u^2\sin^2\theta}{2g}$

u is the initial speed of the discus

So,

$u^2=\dfrac{2\times 9.8\times 100}{\sin^2(30)}\\\\u=\sqrt{7840}\\\\u=88.54\ m/s$

So, the initial speed of the discus is 88.54 m/s.

3 0

3 years ago

PLEASE HELP ASAP!!!! I need to know some machines that put force where you want it

andriy [413]

Answer:

A wheel and axle, force multipliers and a lever.

Explanation:

6 0

2 years ago

Two parallel plates have equal and opposite charges. When the space between the plates is evacuated, the electric field is E= 3.

svetlana [45]

Explanation:

The given data is as follows.

Electric field between plates without dielectric, $E_{1} = 3.50 \times 10^{5} V/m$

Electric field between the plates with dielectric, $E_{2} = 2.40 \times 10^{5} V/m$ .

Permittivity of free space, $\epsilon_{o}$ = $8.85 \times 10^{-12} C^{2}/Nm^{2}$

Now, we will determine the charge density as follows.

$\sigma_{i} = \epsilon_{o}(E_{1} - E_{2})$

= $8.85 \times 10^{-12} \times (3.50 \times 10^{5} - 2.40 \times 10^{5})$

= $9.735 \times 10^{-7} C/m^{2}$

Thus, we can conclude that the charge density on each surface of the dielectric is $9.735 \times 10^{-7} C/m^{2}$ .

6 0

3 years ago

A parcel has a mass of 500 g .calculate its weight (assume the gravitational field strength is 10 N/Kg

Effectus [21]

Answer:

5N

Explanation

convert grams to kg and multipy with 10 (.5 *10)=5N

5 0

3 years ago

31) The basic concept of how a simple motor works is explained by which statement?

Firdavs [7]

Answer:

When a wire that carries electrical current is placed in a magnetic field the wire experiences a force.

Explanation:

The electric motor is a device which convert electrical energy into mechanical energy ie when current carrying conductor is placed in magnetic field it experience a force. Flemings left hand rule explains the direction of the current.

The electric motor works by attraction and repulsion of magnetic field.

So the option d explains basic concept of simple motor ie when when current carrying wire is placed in the magnetic field it experience magnetic repulsive force.

5 0

3 years ago