Answer:
12.495m/s
Explanation:
Horizontal displacement is the range of the projectile motion.
The range is expressed as;
R = 2U/g
U is the speed at which the rock is thrown (initial speed)
g is the acceleration due to gravity.
Given
R = 255cm = 2.55m
g = 9.8m/s²
Required
Speed U
Substitute the given parameters into the formula as shown;
2.55 = 2U/9.8
Cross multiply
2U = 2.55×9.8
2U = 24.99
U = 24.99/2
U = 12.495m/s
Hence the speed that you thew the rock is 12.495m/s
Answer:
2 m = E / c^2 where m is mass of electron
E = h v where v is the frequency ( nu) of the incident photon
E = h c / y where y is the incident wavelength (lambda)
2 m = h / (c y)
y = h / (2 m c) wavelength required
y = 6.62 * 10E-34 / (2 * 9.1 * 10E-31 * 3 * 10E8) m
y = 3.31 / 27.3 E-11 m
y = 1.21 E -12 m = .0121 Angstrom units
Answer:
337k
Explanation:
First, let us find the difference between the given two temperatures.
Difference = 85°C - 21°C
= 64°C
<u>And now we have to write the temperature in kelvins.</u>
To convert Celcius to Kelvins you can add 273 to the temperature in Celcius.
<u>Let us find it now.</u>
64°C + 273 = 337k
Therefore,
64°C ⇒ <u>337k</u>
The question is incomplete! The complete question along with answer and explanation is provided below.
Question:
A 0.5 kg mass moves 40 centimeters up the incline shown in the figure below. The vertical height of the incline is 7 centimeters.
What is the change in the potential energy (in Joules) of the mass as it goes up the incline?
If a force of 1.0 N pulled up and parallel to the surface of the incline is required to raise the mass back to the top of the incline, how much work is done by that force?
Given Information:
Mass = m = 0.5 kg
Horizontal distance = d = 40 cm = 0.4 m
Vertical distance = h = 7 cm = 0.07 m
Normal force = Fn = 1 N
Required Information:
Potential energy = PE = ?
Work done = W = ?
Answer:
Potential energy = 0.343 Joules
Work done = 0.39 N.m
Explanation:
The potential energy is given by
PE = mgh
where m is the mass of the object, h is the vertical distance and g is the gravitational acceleration.
PE = 0.5*9.8*0.07
PE = 0.343 Joules
As you can see in the attached image
sinθ = opposite/hypotenuse
sinθ = 0.07/0.4
θ = sin⁻¹(0.07/0.4)
θ = 10.078°
The horizontal component of the normal force is given by
Fx = Fncos(θ)
Fx = 1*cos(10.078)
Fx = 0.984 N
Work done is given by
W = Fxd
where d is the horizontal distance
W = 0.984*0.4
W = 0.39 N.m
Answer:
21
Explanation:
Weight on the moon is 16.5 % of weight on earth
Weight on moon = 0.165 * 130
Weight on moon = 21 lbs