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3 years ago

A 1451 kg car is traveling at 48.0 km/h. How much kinetic energy does it possess? K.E. =

1 answer:

8 0

   Kinetic energy = (1/2) (mass) (speed)²

BUT . . . in order to use this equation just the way it's written,
the speed has to be in meters per second. So we'll have to
make that conversion.

KE = (1/2) · (1,451 kg) · (48 km/hr)² · (1000 m/km)² · (1 hr/3,600 sec)²

   = (725.5) · (48 · 1000 · 1 / 3,600)² (kg) · (km·m·hr / hr·km·sec)²

   = (725.5) · ( 40/3 )² · ( kg·m² / sec²)

   = 128,978 joules (rounded)

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A telescope can be used to enlarge the diameter of a laser beam and limit diffraction spreading. The laser beam is sent through

Novay_Z [31]

Answer:

Angular spread, $\theta=1.472\times 10^{-7}\ rad$

Explanation:

It is given that,

Wavelength of the light, $\lambda=613\ nm=613\times 10^{-9}\ m$

Diameter of the telescope, D = 5.08 m

The minimum angular spread is given by :

$\theta=\dfrac{1.22\lambda}{D}$

$\theta=\dfrac{1.22\times 613\times 10^{-9}}{5.08}$

$\theta=1.472\times 10^{-7}\ rad$

So, the minimum angular spread of the beam is $1.472\times 10^{-7}\ radian$ . Hence, this is the required solution.

5 0

3 years ago

A 1.25 kg block is attached to a spring with spring constant 17.0 N/m . While the block is sitting at rest, a student hits it wi

Free_Kalibri [48]

Answer:

The amplitude of the subsequent oscillations is 13.3 cm

Explanation:

Given;

mass of the block, m = 1.25 kg

spring constant, k = 17 N/m

speed of the block, v = 49 cm/s = 0.49 m/s

To determine the amplitude of the oscillation.

Apply the principle of conservation of energy;

maximum kinetic energy of the stone when hit = maximum potential energy of spring when displaced

$K.E_{max} = U_{max}\\\\\frac{1}{2} mv^2 = \frac{1}{2} kA^2\\\\where;\\\\A \ is \ the \ maximum \ displacement = amplitude \\\\mv^2 = kA^2\\\\A^2 = \frac{mv^2}{k} \\\\A = \sqrt{\frac{mv^2}{k}} \\\\A = \sqrt{\frac{1.25\ \times \ 0.49^2}{17}} \\\\A = 0.133 \ m\\\\A = 13.3 \ cm$

Therefore, the amplitude of the subsequent oscillations is 13.3 cm

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3 years ago

A large fraction of the ultraviolet (UV) radiation coming from the sun is absorbed by the atmosphere. The main UV absorber in ou

Sergeeva-Olga [200]

Answer:

The wavelength of the radiation absorbed by ozone is 319.83 nm

Explanation:

Given;

frequency of absorbed ultraviolet (UV) radiation, f = 9.38×10¹⁴ Hz

speed of the absorbed ultraviolet (UV) radiation, equals speed of light, v = 3 x 10⁸ m/s

wavelength of the absorbed ultraviolet (UV) radiation, λ = ?

Apply wave equation for speed, frequency and wavelength;

v = fλ

λ = v / f

λ = (3 x 10⁸) / (9.38×10¹⁴)

λ = 3.1983 x 10⁻⁷ m

λ = 319.83 x 10⁻⁹ m

λ = 319.83 nm

Therefore, the wavelength of the radiation absorbed by ozone is 319.83 nm

5 0

4 years ago

An imbalance of _____________ causes an object to be charged.

dezoksy [38]

An imbalance of electrons causes an object to be charged. A charged substance is one that has a net charge that is not zero. If the number of protons and that of electrons is equal in an object, the object is not neutral, but it has zero charge. Loss or gain of electrons determine the charge of an object, when an object loses electrons it becomes positively charged, but when it gains electrons it becomes negatively charged.

5 0

3 years ago

A volleyball player’s hand applies a 39 N force while in contact with a volleyball for 2 seconds. What is the impulse on the bal

nikklg [1K]

Given:
F = 39 N, the force applied
t = 2 s, the time interval in which the force is applied.

By definition, the impulse is
$I = \int_{0}^{2} F(t) dt = \int _{0}^{2} 39dt = 39*2=78 \, N-s$

Answer: 78 N-s

3 0

3 years ago

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