Answer:
20 [N], in the opposite direction of the first force.
Explanation:
We know that newton's second law stipulates that the sum of forces on a body must be equal to the product of mass by acceleration.
![SumF = m*a\\30 + F = 2*5\\F = 30 - (2*5)\\F = - 20 [N]](https://tex.z-dn.net/?f=SumF%20%3D%20m%2Aa%5C%5C30%20%2B%20F%20%3D%202%2A5%5C%5CF%20%3D%2030%20-%20%282%2A5%29%5C%5CF%20%3D%20-%2020%20%5BN%5D)
The negative sign means that the other force acting on the body must be in the opposite direction to the force of 30 [N]
Answer:
First law: kinetic energy is used to turn an electric generator
Second law: some thermal energy is lost to the environment as it travels through the system
Explanation:
The first law of thermodynamics is known as the law of conservation of energy. It states that energy can neither be created nor destroyed but can only be transferred or changed from one form to another. When thermal energy is used to generate electricity, the kinetic energy of the steam is used to turn the electric generator (thereby producing electrical energy).
The second law of thermodynamics states that energy transfer or transformation leads to an increase in entropy resulting in the loss of energy. This law also states that as energy is transferred or transformed, some is lost in a form that is unusable. When thermal energy is used to generate electricity, some of the thermal energy is lost to the environment as it travels through the system.
It is D. X rays have a shorter wavelength than microwaves.
Answer:
time taken with speed 23 km/h will be 1.8 hours or 1 hour 48 minutes
Explanation:
Given:
Time is inversely proportional to the speed
mathematically,
t ∝ (1/r)
let the proportionality constant be 'k'
thus,
t = k/r
therefore, for case 1
time = 3 hr
speed = 14 km/hr
3 = k/14
also,
for case 2
let the time be = t
r = 23 km/h
thus,
we have
t = k/23
on dividing equation 2 by 1
we get

or

or
t = 1.8 hr = or 1 hour 48 minutes ( 0.8 hours × 60 minutes/hour = 48 minutes)