Answer:
a) 6.95 m/s
b) 1.42 seconds
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration due to gravity = 9.81 m/s²

a) The vertical speed when it leaves the ground. is 6.95 m/s

Time taken to reach the maximum height is 0.71 seconds

Time taken to reach the ground from the maximum height is 0.71 seconds
b) Time it stayed in the air is 0.71+0.71 = 1.42 seconds
<span>step 1: energy required to heat coffee
E = m Cp dT
E = energy to heat coffee
m = mass coffee = 225 mL x (0.997 g / mL) = 224g
Cp = heat capacity of coffee = 4.184 J / gK
dT = change in temp of coffee = 62.0 - 25.0 C = 37.0 C
E = (224 g) x (4.184 J / gK) x (37.0 C) = 3.46x10^4 J
step2: find energy of a single photon of the radiation
E = hc / λ
E = energy of the photon
h = planck's constant = 6.626x10^-34 J s
c = speed of light = 3.00x10^8 m/s
λ = wavelength = 11.2 cm = 11.2 cm x (1m / 100 cm) = 0.112 m
E = (6.626x10^-34 J s) x (3.00x10^8 m/s) / (0.112 m) = 1.77x10^-16 J
step3: Number of photons
3.46x10^4 J x ( 1 photon / 1.77x10^-16 J) = 1.95x10^20 photons</span>
Answer:
Distance, d = 112.5 meters
Explanation:
Initially, the bicyclist is at rest, u = 0
Final speed of the bicyclist, v = 30 m/s
Acceleration of the bicycle, 
Let s is the distance travelled by the bicyclist. The third equation of motion is given as :



s = 112.5 meters
So, the distance travelled by the bicyclist is 112.5 meters. Hence, this is the required solution.
Answer: The first one
Explanation: I think it's the first one because it says what is the "least" gravitational potential energy story between the prairie dog and Earth that said resting in its borrow is using less energy
Answer:
V = 3.6385 m/s
θ = 47.46 degrees
Explanation:
the important data in the question is:
Skater 1:
= 39.6 kg
direction: south (axis y)
= 6.21 m/s
Skater 2:
= 52.1 kg
direction: east (axis x)
= 4.33 m/s
Now using the law of the conservation of linear momentum (
and knowing that the collision is inelastic we can do the next equations:
(eq. 1)
(eq. 2)
Where
and
is the velocity of the sistem in x and y after the collision.
Note: the conservation of the linear momentum have to be make once by each axis.
Now, in the (eq. 1) the skater 1 don't have velocity in the axis x, so we can replace
by 0 in the equation and get:
(eq. 1)
also, in the (eq. 2) the skater 2 don't have velocity in the axis y, so we can replace
by 0 in the equation and get:
(eq. 2)
Now, we just replace the data in both equations:
(eq. 1)
(eq. 2)
solving for
and
we have:
= 2.46 m/s
= 2.681 m/s
using the pythagoras theorem we can find the magnitude of the velocity as:
V = 
V = 3.6385 m/s
For find the direction we just need to do this;
θ = 
θ = 47.46 degrees