Answer:
0.8s
Explanation:
Given parameters:
Height of shelf = 3m
Unknown:
Time it will take to hit the ground = ?
Solution:
To solve this problem, we use the expression below;
x = ut + 
gt²
x is the height
u is the initial velocity = 0m/s
g is the acceleration due to gravity = 9.8m/s²
t is the time taken = ?
Now insert the parameters and solve for t;
3 = (0 x t) +( x 9.8 x t²)
3 = 4.9t²
t² = 0.6
t = 0.8s
Answer: 18.9 m
Explanation:
i did the kinematic equation & found the answer.
Answer:The answer is A,B and C
Explanation: it can be use to learn universe behavior,it is also use for the measurements of velocity of galaxy,and is can also be use to indicate,galaxy motion.
Doppler effect,measures the speed which star and galaxy are moving away from us or towards us. It shows the color of wavelength to be either red shift or blue shift.
Answer:
The power output of the first motor is, P = 2.0 x 10⁴ watts
Explanation:
Given data,
The height of the building, h = 10 m
The mass of the elevator, m = 1000 kg
The time duration of the motor to do this work, t = 5.0 s
The force acting on the elevator,
F = m x g
= 1000 x 9.8
= 9800 N
The work done by the elevator,
W = F x h
= 9800 x 10
= 98000 J
The power output of the first motor,
P = W / t
= 98000 / 5
= 19600 watts
= 1.96 x 10⁴ watts
Hence, the power output of the first motor is, P = 2.0 x 10⁴ watts
Answer:
Negative z-direction
Explanation:
First of all, we need to understand the direction of the magnetic force on the proton. This can be determined by using the right hand rule. So we have:
- index finger: direction of the proton, positive x-direction
- middle finger: direction of magnetic field, positive y-direction
- thumb: direction of the force, positive z-direction
In order to balance this magnetic force, the electric force must act in the opposite direction (negative z direction). Since for a proton (positive charge) the force and the electric field have same direction, it means that the electric field must also be in the negative z direction.
