Answer:
99.63 kg
Explanation:
From the force diagram
N = normal force on the worker from the surface of the roof
f = static frictional force = 560 N
θ = angle of the slope = 35
m = mass of the worker
W = weight of the worker = mg
W Cosθ = Component of the weight of worker perpendicular to the surface of roof
W Sinθ = Component of the weight of worker parallel to the surface of roof
From the force diagram, for the worker not to slip, force equation must be
W Sinθ = f
mg Sinθ = f
m (9.8) Sin35 = 560
m = 99.63 kg
Answer:
4. The direct sunlight received by creosote bush in the desert area (in kWh/m2) during a 12 month period
Explanation:
The creosote bush depends on sunlight to produce the food they require through photosynthesis. The shade from the solar panels would reduce the amount of sunlight that the bush receives. This would increase the mortality of the bush.
In order to test the hypothesis the student must record the direct sunlight received by creosote bush in the desert area (in kWh/m2) during a 12 month period. If the plants receive sunlight less than the above amount the plants should start dying. If not then the hypothesis is false.
Hence, the answer is 4. The direct sunlight received by creosote bush in the desert area (in kWh/m2) during a 12 month period.
Answer:
5.72 seconds
848.27 m/s
97.94 m
Explanation:
t = Time taken
u = Initial velocity = 15 m/s
v = Final velocity
s = Displacement
a = Acceleration due to gravity = 9.81 m/s²

Time taken to reach maximum height is 0.97 seconds

So, the stone would travel 11.47 m up
So, total height stone would fall is 75+11.47 = 86.47 m
Total distance travelled by the stone would be 75+11.47+11.47 = 97.94 m

Time taken by the stone to travel 86.47 m to the water is is 4.2 seconds
The stone reaches the water after 4.2+1.52 = 5.72 seconds after throwing the stone

Speed just before hitting the water is 848.27 m/s
Answer:
<em>a) 3.56 x 10^22 N</em>
<em>b) 3.56 x 10^22 N</em>
<em></em>
Explanation:
Mass of the sun M = 2 x 10^30 kg
mass of the Earth m = 6 x 10^24 kg
Distance between the sun and the Earth R = 1.5 x 10^11 m
From Newton's law,
F = 
where F is the gravitational force between the sun and the Earth
G is the gravitational constant = 6.67 × 10^-11 m^3 kg^-1 s^-2
m is the mass of the Earth
M is the mass of the sun
R is the distance between the sun and the Earth.
Substituting values, we have
F =
= <em>3.56 x 10^22 N</em>
<em></em>
A) The force exerted by the sun on the Earth is equal to the force exerted by the Earth on the Sun also, and the force is equal to <em>3.56 x 10^22 N</em>
b) The force exerted by the Earth on the Sun = <em>3.56 x 10^22 N</em>
Answer:
c
Explanation:
If you double your speed, the energy dissipated in a crash is four times greater
Because impact increases with square of increase in speed.