It woul be 0 because it is not moving. It is staying at a constant rate.
Gravity is an example of friction. If we didn't have gravity, we would be flying all over the place. Also, friction keeps us from sliding on the ground and falling.
Answer:
v = 60.62 km/h
Explanation:
Kinetic energy
Kinetic energy is that which is due to the movement of bodies and is calculted like this:
K = (1/2)mv² Formula (1)
Where:
K : Kinetic energy (J)
m: mass (kg)
v : speed (m/s)
Data for the truck
m = 15000 kg
v= 21 km/h = 21 *(1000m)/ (3600s)
v= 5.83 m/s
Calculation of the kinetic energy of the truck
We replace data in the formula (1)
K = (1/2)mv²
K = (1/2)(15000)(5.83)²
K = 255208.3 J
Data for the compact car
K = 255208.3 J = 255208.3 (N*m)
m = 1800 kg
Calculation of the speed of the compact car
We replace data in the formula (1)
K = (1/2)mv²
255208.3 = (1/2)( 1800)(v)²
255208.3 = ( 900)(v)²
v² = 255208.3 / ( 900)
![v= \sqrt{\frac{255208.3}{900} }](https://tex.z-dn.net/?f=v%3D%20%5Csqrt%7B%5Cfrac%7B255208.3%7D%7B900%7D%20%7D)
v = 16.84 m/s
1 km = 1000 m
1 h = 3600 s
v = 16.84*(3600/1000)km/h
v = 60.62 km/h
Answer:
a = 50 [m/s²]
Explanation:
This type of problem can be solved using Newton's second law, which tells us that the sum of forces on a body is equal to the product of mass by acceleration.
∑F = m*a
where:
F = force =25 [N] (units of Newtons)
m = mass = 0.5 [kg]
a = acceleration [m/s²]
![a=F/m\\a=25/0.5\\a= 50 [m/s^{2}]](https://tex.z-dn.net/?f=a%3DF%2Fm%5C%5Ca%3D25%2F0.5%5C%5Ca%3D%2050%20%5Bm%2Fs%5E%7B2%7D%5D)
Answer:
Work done, W =1520 J
Explanation:
We have,
The brakes on a bicycle apply 95 N of force to the wheels. When the brakes are applied, the bicycle comes to a stop in 16 m.
It is required to find the work done by the brakes on the wheels. We know that the product of force and displacement is equal to the work done. It is given by :
![W=Fd\\\\W=95\times 16\\\\W=1520\ J](https://tex.z-dn.net/?f=W%3DFd%5C%5C%5C%5CW%3D95%5Ctimes%2016%5C%5C%5C%5CW%3D1520%5C%20J)
So, the work done by the brakes is 1520 J.