What amount of temperature do you need to make a metamorphic rock?

Net force is the sum of all forces acting on an object. For example, in a tug of war, when one team is pulling the rope with a f

melisa1 [442]

Answer:

If there are equal forces in both directions and there is no motion, the net force is 0 Newtons. This is because you'd be subtracting 100 from 100 which just equals 0.

5 0

3 years ago

I would like help with this physics problem

Darina [25.2K]

(a) This is a freefall problem in disguise - when the ball returns to its original position, it will be going at the same speed but in the opposite direction. So the ball's final velocity is the negative of its initial velocity.

Recall that

$v_f=v_i+at$

We have $v_f=-v_i$ , so that

$-2v_i=at\implies-2\left(8\,\dfrac{\mathrm m}{\mathrm s}\right)=\left(-2\,\dfrac{\mathrm m}{\mathrm s^2}\right)t\implies t=8\,\mathrm s$

(b) The speed of the ball at the start and at the end of the roll are the same 8 m/s, so the average speed is also 8 m/s.

(c) The ball's average velocity is 0. Average velocity is given by $\dfrac{v_i+v_f}2$ , and we know that $v_f=-v_i$ .

(d) The position of the ball $x_f$ at time $t$ is given by

$x_f=x_i+v_it+\dfrac12at^2$

Take the starting position to be the origin, $x_i=0$ . Then after 6 seconds,

$x_f=\left(8\,\dfrac{\mathrm m}{\mathrm s}\right)(6\,\mathrm s)+\dfrac12\left(-2\,\dfrac{\mathrm m}{\mathrm s^2}\right)(6\,\mathrm s)^2=42\,\mathrm m$

so the ball is 42 m away from where it started.

We're not asked to say in which direction it's moving at this point, but just out of curiosity we can determine that too:

$x_f-x_i=\dfrac{v_i+v_f}2t\implies42\,\mathrm m=\dfrac{8\,\frac{\mathrm m}{\mathrm s}+v_f}2(6\,\mathrm s)\implies v_f=6\,\dfrac{\mathrm m}{\mathrm s}$

Since the velocity is positive, the ball is still moving up the incline.

8 0

3 years ago

A supertanker ( = 1.70 × 108 kg) is moving with a constant velocity. Its engines generate a forward thrust of 7.40 × 105 N. Dete

a_sh-v [17]

Answer:

(a) 0 (b) $F=1.67\times 10^9\ N$

Explanation:

Given that,

Mass of a supertanker, $m=1.7\times 10^8\ kg$

The engine of a generate a forward thrust of, $F=7.4\times 10^5\ N$

(a) As the supertanker is moving with a constant velocity. We need to find the magnitude of the resistive force exerted on the tanker by the water. It is given by :

F = ma, a is the acceleration

For constant velocity, a = 0

So, F = 0

(b) The magnitude of the upward buoyant force exerted on the tanker by the water is equal to the weight of the ship.

F = mg

$F=1.7\times 10^8\times 9.8\\\\F=1.67\times 10^9\ N$