Answer:
0.6375 cm
Explanation:
coefficient of linear expansion of copper, α =
Lo = 25 m
Δ T = 25 degree C
According to the formula of thermal expansion which is linear in nature is given by
Where, ΔL be the change in length
=0.6375 cm
1) Acceleration of the sled
The acceleration of the sled is given by the net force acting in the direction parallel to the incline. There are two forces acting along this direction: the component of the weight parallel to the ramp (downward) and the friction (upward). Therefore, the net force acting in this direction is
And the acceleration is given by Newton's second law:
2) Normal force
The normal force acting on the sled is equal to the component of the weight perpendicular to the incline, therefore:
Answer:
f = 0.84 m
Explanation:
given,
near point of the distance from eye(d_i) = 0.60 m
distance he can read (d_o)= 0.350 m
focal length of the contact lens = ?
now,
Using lens formula
f = 0.84 m
Hence, The focal length of the contact lens that person needed is equal to
f = 0.84 m
Answer:
This ball will attain the same range at 60°.
Explanation:
Projectile motion: when an object is thrown in such a way that it form an angle with horizon, the force act on it that is the acceleration due gravity. This type of motion is known as projectile motion.
Range: The horizontal distance is covered by an object.
Range
u = initial velocity = 40 m/s
θ = 30°
g = gravity =9.8 m/s²
Next,
Range and u = 40 m/s
This ball will attain the same range at 60°.
Answer:
1000 cm.
Explanation:
To obtain the estimated tree height :
(Height of rod / length of rod shadow) = (height of tree / length of tree shadow)
Substituting values into the formula :
(150cm / 120 cm) = (height of tree / 800 cm)
Using cross multiplication :
Height of tree * 120 = 150 * 800
Height of tree = (150 * 800) / 120
Height of tree = 120,000 / 120
Height of tree = 1000
Hence, estimate height of tree = 1000 cm