Answer:
a. keeps its speed for a short while, then slows and stops. slows steadily until it stops.
Explanation:
Since the tension in the rope, t is greater than the kinetic friction fk, the box is moving forward because there is a net force on it. That is, t - fk = f = ma.
Since there is a net force, there is an acceleration and thus an increasing velocity.
When the rope breaks, the tension, t = 0. So, t - fk = 0 - fk = -fk = ma'.
Now, the net force acting on the box is friction in the opposite direction. This force tends to slow the box down from its initial velocity at acceleration, 'a' until its velocity is zero, where it stops. Since the frictional force is constant, the acceleration, a' on the box is thus constant and the box undergoes uniform deceleration until its velocity is zero.
<u>So, the box keeps its speed for a short while, then slows and stops. slows steadily until it stops.</u>
So, the answer is a.
Acceleration is the
rate of change of velocity, a body moving with uniform velocity does not
possess acceleration at all i.e. acceleration is zero
Answer:
735N
Explanation:
Weight is a measurement of force.
F = Force
m = mass
a = acceleration
F = m*a
F = 75kg*9.8m/s²
F = 735N
The car with the engine that has the most power
Answer:
Melt.
Explanation:
When rocks melt, they do so slowly and gradually because most rocks are made of several minerals, which all have different melting points; moreover, the physical and chemical relationships controlling the melting are complex. As a rock melts, for example, its volume changes. When enough rock is melted, the small globules of melt link up and soften the rock.
Under normal conditions, mantle rock like peridotite shouldn't melt in the Earth's upper mantle. However, by adding water you can lower the melting point of the rock. Alternatively, by decompressing the rock, you can bring it to a pressure where the melting point is lower. In both cases, basalt magma will form and considering it is hotter and less dense than the surrounding rock, it will percolate towards the surface and some of that erupts.
