Answer:
Explanation:
Average velocity is found in the total displacement experienced in the trip divided by the total time it took to make this trip. If, for the first 2.0 hours, the car travels at 60 km/hr, then in 2.0 hours the car can travel 120 km; if it then travels for 3.0 at 85 km/hr, it can travel 255 km in the same direction. The total time this took was 5.0 hours. So doing the math and rounding correctly by following the rules for the adding and subtracting of sig fig's:
If you do not round when you add, the average velocity is 75 km/hr
Explanation:
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. There are several types of friction: Dry friction is a force that opposes the relative lateral motion of two solid surfaces in
Answer:
105.1N
Explanation:
According to the newton second law
Since the acceleration is zero, then;
Since;
Given the following
mass of ladder m = 14kg
acceleration due to gravity g = 9.8m/s²
θ = 50°
Substitute
Hence the magnitude of the friction force (in N) exerted on the ladder in the point of contact with the horizontal surface is 105.1N
The change in potential energy of an object is given by
where
m is the mass of the object
g is the gravitational acceleration
is the increase in altitude of the object
In our problem,
is the mass of the book,
and
is the increase in altitude of the book, so its variation of potential energy is
