Choose the correct statement regarding energy production in the interior of a star and energy production in a power plant.

If F1 = 390 N and F2 = 550 N , determine the angle θ(0∘≤θ≤180∘) between them, so that the resultant force has a magnitude of FR

Nadya [2.5K]

Answer:

Explanation:

R² = F₁² + F₂² + 2F₁F₂ Cosθ , R is resultant force , θ is angle between them

780² = 390² + 550² + 2 x 390 x 550 Cosθ

608400 = 152100 + 302500 + 429000 Cosθ

Cosθ = .3585

θ = 69 degree.

5 0

3 years ago

What is the force of gravitational attraction between an object with a mass of 100 kg and another object that has a mass of 300

HACTEHA [7]

Answer:

5 x 10⁻⁷N

Explanation:

Given parameters:

Mass of object 1 = 100kg

Mass of object 2 = 300kg

Distance = 2m

Unknown:

Force of gravitational attraction between the objects = ?

Solution:

From Newton's law of universal gravitation we derive an expression:

Fg = $\frac{G m_{1} m_{2} }{r^{2} }$

G is the universal gravitation constant = 6.67 x 10⁻¹¹

m is the mass

r is the distance between the bodies

Now insert the parameters and solve;

Fg = 6.67 x 10⁻¹¹ x $\frac{100 x 300}{2^{2} }$ = 5 x 10⁻⁷N

3 0

3 years ago

What force must be provided to accelerate a 64-lb object upward at a rate of 2 ft/s2? (Use g = 32 ft/s2.)

vovikov84 [41]

Answer:

The force that must be provided to accelerate the object = 302.196 N

Explanation:

Force: Force can be defined as the product of mass and acceleration. The S.I unit of force is Newton (N).

Ft - W = ma............ Equation 1

Ft = W + ma .......... Equation 2

Where Ft = force provided, W = weight of the object, m= mass of the object, a = acceleration of the object.

Given: mass = 64 lb, g = 32 ft/s² a = 2 ft/s²

Conversion: (i) from 64 pounds to Kg = 64/2.2046

= 29.03 kg

(ii) from 2 ft/s² to m/s² = 0.3048 × 2 = 0.6098 m/s²

(iii) from 32 ft/s² to m/s² = 0.3048×32 = 9.8 m/s².

and W = mg = 29.03 × 9.8 = 284.494 N,

Substituting these values into equation 2,

Ft = 284.494 + 29.03×0.6098

Ft = 284.494 + 17.7

Ft = 302.196 N

Therefore, the force that must be provided to accelerate the object = 302.196 N

8 0

4 years ago

An object slides on a level surface in the +x direction. It slows and comes to a stop with a constant acceleration of -2.45 m/s2

Stolb23 [73]

Answer:

uk = 0.25

Explanation:

Given:-

- An object comes to stop with acceleration, a = -2.45 m/s^2

Find:-

What is the coefficient of kinetic friction between the object and the floor?

Solution:-

- Assuming the object has mass (m) that slides over a rough surface with coefficient of kinetic friction (uk). There is only Frictional force (Ff) acting in the horizontal axis on the object opposing the motion (-x direction).

- We will apply equilibrium equation on the object in vertical direction.

N - m*g = 0

N = m*g

Where, N : Contact force exerted by the surface on the floor

g : Gravitational acceleration constant = 9.81 m/s^2

- Now apply Newton's second law of motion in the horizontal ( x-direction ):

- Ff = m*a

- The frictional force is related to contact force (N) by the following expression:

Ff = uk*N

- Substitute the 1st and 3rd expressions in the 2nd equation:

uk*m*g = -m*a

uk = a / g

- Plug in the values and solve for uk:

uk = - (-2.45) / 9.81

uk = 0.25

8 0

3 years ago

Light travelling in one material enters another material in which it travels faster. The light wave will:

Free_Kalibri [48]

The light will change its direction and bend away from the normal.

8 0

4 years ago