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1 year ago

Calculate the kinetic energy in joules of a ball of mass 40g moving at a velocity of 4 metres per second

1 answer:

6 0

Given : A ball of mass 40 g moving at a velocity of 4 m/s.
To find : Calculate the kinetic energy in joules ?
Solution :
The kinetic energy formula is given by,

where, v is the velocity v=4 m/s
m is the mass m=40 g
Convert g into kg,

Substitute the values,

Therefore, the kinetic energy is 0.32 Joules.

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Coherent light that contains two wavelengths, 660 nm and 470 nm , passes through two narrow slits with a separation of 0.280 mm

bekas [8.4K]

Answer:

λ1 = 0.0129m = 1.29cm

λ2 = 0.00923m = 0.92 cm

Explanation:

To find the distance between the first order bright fringe and the central peak, can be calculated by using the following formula:

$y_m=\frac{m\lambda D}{d}$ (1)

m: order of the bright fringe = 1

λ: wavelength of the light = 660 nm, 470 nm

D: distance from the screen = 5.50 m

d: distance between slits = 0.280mm = 0.280 *10^⁻3 m

ym: height of the m-th fringe

You replace the values of the variables in the equation (1) for each wavelength:

For λ = 660 nm = 660*10^-9 m

$y_1=\frac{(1)(660*10^{-9}m)(5.50m)}{0.280*10^{-3}m}=0.0129m=1.29cm$

For λ = 470 nm = 470*10^-9 m

$y_1=\frac{(1)(470*10^{-9}m)(5.50m)}{0.280*10^{-3}m}=0.00923m=0.92cm$

7 0

3 years ago

A spiracle polish metallic ball is uses a diverging mirror with a focal length of -20 cm a bird 25 cm tall standing 50 cm away L

Aleksandr-060686 [28]

Answer:

1/f = 1/i + 1/o thin lens equation

1/i = 1/f - 1/o

i = o * f / ( o - f) = 50 * (-20) / (50 - (-20)) = -14.3 cm

The final image is erect and 14.3 cm behind the curved surface

M = -o / i = 14.3 / 50 = .29 magnificaton of object

S = .29 * 25 cm = 7.1 cm appearance of bird in mirror (height)

5 0

2 years ago

A ball with a mass of 275 g is dropped from rest, hits the floor and rebounds upward. If the ball hits the floor with a speed of

Alla [95]

Answer:

Change in momentum is 1.1275 kg-m/s

Explanation:

It is given that,

Mass of the ball, m = 274 g = 0.274 kg

It hits the floor and rebounds upwards.

The ball hits the floor with a speed of 2.40 m/s i.e. u = -2.40 m/s (-ve because the ball hits the ground)

It rebounds with a speed of 1.7 m/s i.e. v = 1.7 m/s (+ve because the ball rebounds in upward direction)

We have to find the change in the ball's momentum. It is given by :

$\Delta p=p_f-p_i$

$\Delta p=m(v-u)$

$\Delta p=0.275\ kg(1.7\ m/s-(-2.4\ m/s))$

$\Delta p=1.1275\ kg-m/s$

So, the change in the momentum is 1.1275 kg-m/s

3 0

2 years ago

What is an essential characteristic of an object in equilibrium

Alecsey [184]

Answer:

The essential characteristics of an object in equilibrium is acceleration of the object must be zero.

Explanation:

Equilibrium: An object acted upon by several forces is said to be in equilibrium if it does no it moves or rotate. Equilibrium can be defined as the state of stability of an object.

Condition for equilibrium

(i) The resultant force acting on the object must me equal to zero.

(ii) The sum of moment acting on the object must be equal to zero.

But.

F = ma..................... Equation 1

Where F = net force , m = mass, a = acceleration.

from the equation above,

For F = 0 N, a must be equal to zero.

<em>From the above, the essential characteristics of an object in equilibrium is acceleration must be zero</em>

6 0

2 years ago

In 2013, the world record depth for free diving without assistance was 101 m. What is the pressure in the water (assumed freshwa