Answer:
1. Formula = distance/time
D= 112.0 meters, time =4 secs
Speed = d/t =112.0/4
= 28m/s
2.Formula = distance/time
D= 1/4 x 16093.44 m
= 402.35m
Time = 15secs
Speed= d/t
= 402.35/15
=26m/s
If the type of friction is sliding friction, it may be increased by increasing the roughness of the surface and may be decreased by smoothing the surface or applying a lubricant.
Answer:
Heat of reaction or enthalpy of reaction (ΔH)
Explanation:
The heat of reaction or enthalpy of reaction (ΔH) is the amount of heat energy that the system must release or absorb so that the temperature remains constant throughout the chemical reaction process. In other words, the heat of reaction or enthalpy of reaction (ΔH) is the change in the enthalpy of a chemical reaction (the energy absorbed or released into it) that occurs at a constant pressure.
Then, this energy can be observed in the following way:
Every substance has a quantity of energy stored in its links. When the energy contained in the reagents is greater than that contained in the products, the reaction is exothermic because energy release occurs. When the energy contained in the reagents is less than that contained in the products, an endothermic reaction occurs because energy absorption occurs.
That energy contained in the substances is called enthalpy (H).
Then the enthalpy can be defined as the difference between the sum of the enthalpies of the products and the sum of the enthalpies of the reactants.
Initially sled is moving with uniform velocity which means the net force must be balanced on the sled

So it is given that applied force on the sled is 200 N and sled is not accelerating so friction force must be 200 N.

Now suddenly it starts with 600 N applied force due to which it will accelerate and this can calculated by Newton's II law




So in this case the sled ill start accelerating with acceleration 