Answer:
Explanation:
The boy throw the pencil upward at a speed of 6.33 m/s
Then,
Initial velocity of throw is 6.33 m/s
u = 6.33 m/s.
Time to reach a maximum height of 1.25m
h = 1.25m
Note: at maximum height, the final velocity is zero
v = 0m/s
Acceleration due to gravity is
g = 9.81m/s²
We want to calculate time to reach maximum height
t = ?
Then, applying equation of motion
v = u + gt
But since it is against gravity, then, g is negaive
Then,
v = u - gt
0 = 6.33 - 9.81t
-6.33 = -9.81t
Then,
t = -6.33 / -9.81
t = 0.645 seconds
The wavelength and frequency of light are closely related. The higher the frequency, the shorter the wavelength. Because all light waves move through a vacuum at the same speed, the number of wave crests passing by a given point in one second depends on the wavelength. That number, also known as the frequency, will be larger for a short-wavelength wave than for a long-wavelength wave.
Answer:
A. Distance over which the force is applied
Explanation:
As we know that in pulley system the mass of the car is balanced by the tension in the string
so here we will have
so here in order to decrease the force needed to lift the car we have to increase Distance over which the force is applied
So here if we increase the distance over which force is applied then it will reduce the effort applied by us in this pulley system as the torque will be more if the distance is more.
Answer:
The work done in winding the spring gets stored in the wound up spring in the form of elastic potential energy (i.e potential energy due to change in shape). ... During this process, the potential energy stored in it gets converted to kinetic energy. This turns the wheels of the toy car.
Explanation:
According to Stefan-Boltzmann Law, the thermal energy radiated by a radiator per second per unit area is proportional to the fourth power of the absolute temperature. It is given by;
P/A = σ T⁴ j/m²s
Where; P is the power, A is the area in square Meters, T is temperature in kelvin and σ is the Stefan-Boltzmann constant, ( 5.67 × 10^-8 watt/m²K⁴)
Therefore;
Power/square meter = (5.67 × 10^-8) × (3000)⁴
= 4.59 × 10^6 Watts/square meter
