Answer:
The velocity will be "76.8 m/s".
Explanation:
The given values are:
Acceleration,
a = 2.4 m/s²
Time,
t = 32 seconds
By equation of motion,
⇒ 
On substituting the values, we get
⇒ 
⇒ 
⇒ 
<span>Answer:
Using 1/f = 1/d' + 1/d ...(where d' object distance and d is image distance)
1/4 = 1/7 + 1/d
1/4 - 1/7 = 1/d
3/28 = 1/d
d = 28/3
d = 9.33 cm</span>
Answer:
The weight if the block is 10Newtons
Explanation:
The weight of any object is quantity of matter the object contains and it is always acting downwards on such body. This shows that the object is under the influence of gravity.
The weight of an object is calculated as mass of the object × its acceleration due to gravity
W = mg
Give the mass of the brick to be 1kg
g is the acceleration due to gravity = 10m/s²
Weight of the object = 1 × 10
= 10kgm/s² or 10Newtons
Answer:
A) d = 11.8m
B) d = 4.293 m
Explanation:
A) We are told that the angle of incidence;θ_i = 70°.
Now, if refraction doesn't occur, the angle of the light continues to be 70° in the water relative to the normal. Thus;
tan 70° = d/4.3m
Where d is the distance from point B at which the laser beam would strike the lakebottom.
So,d = 4.3*tan70
d = 11.8m
B) Since the light is moving from air (n1=1.00) to water (n2=1.33), we can use Snell's law to find the angle of refraction(θ_r)
So,
n1*sinθ_i = n2*sinθ_r
Thus; sinθ_r = (n1*sinθ_i)/n2
sinθ_r = (1 * sin70)/1.33
sinθ_r = 0.7065
θ_r = sin^(-1)0.7065
θ_r = 44.95°
Thus; xonsidering refraction, distance from point B at which the laser beam strikes the lake-bottom is calculated from;
d = 4.3 tan44.95
d = 4.293 m
Answer:
72km
Explanation:
30 mins --> 30 x 60 s = 1800 s
Distance --> Speed x Time
= 40m/s x 1800s
= 72 000 m
= 72 km (1km is 1000m)
