Let \text{Let} Let
m 1 = 50 t = 50000 k g m_1 = 50 t = 50000kg m 1 = 50 t = 50000 k g
m 2 = 10 t = 100000 k g m_2 = 10 t = 100000kg m 2 = 10 t = 100000 k g
v 0 = 0 ; v 1 = 20 m s ; t = 5 s v_0=0;v_1=20\frac{m}{s};t=5s v 0 = 0 ; v 1 = 20 s m ; t = 5 s
μ = 5 N t = 0.005 N k g \mu = 5\frac{N}{t}= 0.005\frac{N}{kg} μ = 5 t N = 0.005 k g N
F e x − Force exerted by the engine F_{ex}-\text{Force exerted by the engine} F e x − Force exerted by the engine
F f r − Friction force F_{fr}-\text{Friction force} F f r − Friction force
F = m a ; F = F e x − F f r F = ma;F = F_{ex}-F_{fr} F = ma ; F = F e x − F f r
a = v 1 − v 0 t = 20 − 0 5 = 4 m s 2 a = \frac{v_1-v_0}{t}= \frac{20-0}{5}=4\frac{m}{s^2} a = t v 1 − v 0 = 5 20 − 0 = 4 s 2 m
F f r = μ ∗ m F_{fr}= \mu*m F f r = μ ∗ m
m = m 1 + m 2 m = m_1+m_2 m = m 1 + m 2
a ) a) a )
F e x = F + F f r = m a + μ m = 200250 N F_{ex}=F+F_{fr}= ma+\mu m=200250N F e x = F + F f r = ma + μ m = 200250 N
b ) b) b )
S = v 0 t + a t 2 2 S = v_0t +\frac{at^2}{2} S = v 0 t + 2 a t 2
v 0 = 0 v_0 = 0 v 0 = 0
t = 2 S a = 2 ∗ 100 4 = 7.07 m s t =\sqrt{\frac{2S}{a}}=\sqrt{\frac{2*100}{4}}=7.07\frac{m}{s} t = a 2 S = 4 2 ∗ 100 = 7.07 s m
Answer: \text{Answer:} Answer:
a ) F e x = 200250 N a) F_{ex}=200250N a ) F e x = 200250 N
b ) t = 7.07 m s b)t =7.07\frac{m}{s} b ) t = 7.07 s m
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