Answer:
<em>a. The rock takes 2.02 seconds to hit the ground</em>
<em>b. The rock lands at 20,2 m from the base of the cliff</em>
Explanation:
Horizontal motion occurs when an object is thrown horizontally with an initial speed v from a height h above the ground. When it happens, the object moves through a curved path determined by gravity until it hits the ground.
The time taken by the object to hit the ground is calculated by:

The range is defined as the maximum horizontal distance traveled by the object and it can be calculated as follows:

The man is standing on the edge of the h=20 m cliff and throws a rock with a horizontal speed of v=10 m/s.
a,
The time taken by the rock to reach the ground is:


t = 2.02 s
The rock takes 2.02 seconds to hit the ground
b.
The range is calculated now:

d = 20.2 m
The rock lands at 20,2 m from the base of the cliff
Velocity is the rate of change of position with respect to time, whereas acceleration is the rate of change of velocity. Both are vector quantities (and so also have a specified direction), but the units of velocity are meters per second while the units of acceleration are meters per second squared.
Assume the snow is uniform, and horizontal.
Given:
coefficient of kinetic friction = 0.10 = muK
weight of sled = 48 N
weight of rider = 660 N
normal force on of sled with rider = 48+660 N = 708 N = N
Force required to maintain a uniform speed
= coefficient of kinetic friction * normal force
= muK * N
= 0.10 * 708 N
=70.8 N
Note: it takes more than 70.8 N to start the sled in motion, because static friction is in general greater than kinetic friction.
Answer:
94.1 m
Explanation:
From Coulombs law,
F = Gm1m2/r²................... Equation 1
where F = force, m1 = first mass, m2 = second mass, G = universal constant, r = distance of separation.
Make r the subject of the equation,
r = √(Gm1m2/F)................. Equation 2
Given: F = 7×10² N, m1 = 15×10⁷ kg, m2 = 62×10⁷ kg,
Constant: G = 6.67×10⁻¹¹ Nm²/kg²
Substitute into equation 2
r = √( 6.67×10⁻¹¹×15×10⁷×62×10⁷/7×10²)
r √(886.16×10)
r √(88.616×10²)
r = 9.41×10
r = 94.1 m.
Hence the distance of separation = 94.1 m
Draw a circuit that contains 2 batteries, three lights in parallel and a switch that controls the whole circuit.