Answer:
option B
Explanation:
given,
height of building = 0.1 km
ball strikes horizontally to ground at = 65 m
speed at which the ball strike = ?
vertical velocity = 0 m/s
time at which the ball strike



t = 4.53 s
vertical velocity at the time 4.53 s = g × t = 9.8 × 4.53 = 44.39 m/s
horizontal velocity =
=14.35 m/s
speed of the ball =
= 46.65 m/s
hence, the speed of the ball just before it strike the ground = 47 m/s
The correct answer is option B
Answer:
Explanation:
Given that,.
A house hold power consumption is
475 KWh
Gas used is
135 thermal gas for month
Given that, 1 thermal = 29.3 KWh
Then,
135 thermal = 135 × 29.3 = 3955.5 KWh
So, total power used is
P = 475 + 3955.5
P =4430.5 KWh
Since 1 hr = 3600 seconds
So, the energy consumed for 1hr is
1KW = 1000W
P = energy / time
Energy = Power × time
E = 4430.5 KWhr × 1000W / KW × 3600s / hr
E = 1.595 × 10^10 J
So, using Albert Einstein relativity equation
E = mc²
m = E / c²
c is speed of light = 3 × 10^8 m/s
m = 1.595 × 10^10 / (3 × 10^8)²
m = 1.77 × 10^-7 kg
Then,
1 kg = 10^6 mg
m = 1.77 × 10^-7 kg × 10^6 mg / kg
m = 0.177mg
m ≈ 0.18 mg
It causes or makes a magnetic field.
Answer:
The force needed is the weight of the rock minus the buoyant force.
Explanation: