Answer:
the average speed in annual work out is 46.5
Answer:
T_final = 279.4 [°C]
Explanation:
In order to solve this problem, we must use the following equation of thermal energy.
where:
Q = heat = 9457 [cal]
m = mass = 79 [g] = 0.079 [kg]
Cp = specific heat = 0.5 [cal/g*°C]
T_initial = initial temperature = 40 [°C]
T_final = final temperature [°C]
![9457 = 79*0.5*(T_{f}-40)\\239.41=T_{f}-40\\\\T_{f}=279.4[C]](https://tex.z-dn.net/?f=9457%20%3D%2079%2A0.5%2A%28T_%7Bf%7D-40%29%5C%5C239.41%3DT_%7Bf%7D-40%5C%5C%5C%5CT_%7Bf%7D%3D279.4%5BC%5D)
Answer:
Force of friction is (-30 N).
Explanation:
The force applied on the box across the floor is 30 N.
The force of gravity is (-8 N) and the the normal force is 8 N.
It is based on Newton's third law of motion. Newton's third law of motion states that the force acting on object 1 to object 2 is equal in magnitude of the force from object 2 to 1 but in opposite direction.
Here there is force of 30 N is applied in horizontal direction. The frictional force act in opposite direction. So, the force of friction is -30 N so that box across the floor.
